A boy im50kg at rest on a skateboard is pushed by another boy who exerts a force of 200 N on him. If the first boy's
final velocity is 8 m/s, what was the contact time?
seconds

Answers

Answer 1

Answer:

Time, t = 2 seconds

Explanation:

Given the following data;

Mass, m = 50 kg

Initial velocity, u = 0 m/s (since it's starting from rest).

Final velocity, v = 8 m/s

Force, F = 200 N

To find the time, we would use the following formula;

[tex] F = \frac {m(v - u)}{t} [/tex]

Making time, t the subject of formula, we have;

[tex] t = \frac {m(v - u)}{F} [/tex]

Substituting into the formula, we have;

[tex] t = \frac {50(8 - 0)}{200} [/tex]

[tex] t = \frac {50*(8)}{200} [/tex]

[tex] t = \frac {400}{200} [/tex]

Time, t = 2 seconds


Related Questions

A 1.25 kg block is attached to a spring with spring constant 17.0 N/m . While the block is sitting at rest, a student hits it with a hammer and almost instantaneously gives it a speed of 49.0 cm/s . What are You may want to review (Pages 400 - 401) . Part A The amplitude of the subsequent oscillations

Answers

Answer:

The amplitude of the subsequent oscillations is 13.3 cm

Explanation:

Given;

mass of the block, m = 1.25 kg

spring constant, k = 17 N/m

speed of the block, v = 49 cm/s = 0.49 m/s

To determine the amplitude of the oscillation.

Apply the principle of conservation of energy;

maximum kinetic energy of the stone when hit = maximum potential energy of spring when displaced

[tex]K.E_{max} = U_{max}\\\\\frac{1}{2} mv^2 = \frac{1}{2} kA^2\\\\where;\\\\A \ is \ the \ maximum \ displacement = amplitude \\\\mv^2 = kA^2\\\\A^2 = \frac{mv^2}{k} \\\\A = \sqrt{\frac{mv^2}{k}} \\\\A = \sqrt{\frac{1.25\ \times \ 0.49^2}{17}} \\\\A = 0.133 \ m\\\\A = 13.3 \ cm[/tex]

Therefore, the amplitude of the subsequent oscillations is 13.3 cm

The brakes in car A and car B stop working and they need to stop. Car A and car B have the same mass. Car A is traveling at 30 miles per hour, smashes into a big wall, and is brought to rest in a collision that lasts for a fraction of a second. Car B was also traveling at 30 mph but it drives out into a field of grasses and sand and finally comes to rest after a bumpy 20 second ride. Which car gets the larger impulse?

Answers

Answer:

Both have equal impulse.

Explanation:

Let the mass of cars be m.

Then the Force acting on each of them for taking them to state of rest:

(Using Newton's second law of motion)

[tex]F_A=\frac{m\times (0-30)}{\Delta t_A}[/tex]

[tex]F_A=-30\frac{m}{\Delta t_A}[/tex] ...................................(1) (negative sign is associated with direction, here we are concerned about the magnitude only)

[tex]F_B=\frac{m\times (0-30)}{\Delta t_B}[/tex]

[tex]F_B=-30\frac{m}{\Delta t_B}[/tex] ...................................(2)

[tex]\because \Delta t_A<\Delta t_B[/tex]

[tex]\therefore F_A>F_B[/tex]

We know that impulse is given as:

[tex]J=F\times \Delta t[/tex] ........................................(3)

So, from eq. (1), (2) & (3)

[tex]J_A=F_A\times \Delta t_A[/tex]

[tex]J_A=-30m[/tex]

&

[tex]J_B=F_B\times\Delta t_A[/tex]

[tex]J_B=-30m[/tex]

Hence both have equal impulse.

A hot-air balloon is rising upward with a constant speed of 2.85 m/s. When the balloon is 2.50 m above the ground, the balloonist accidentally drops a compass over the side of the balloon. How much time elapses before the compass hits the ground

Answers

Answer:

Explanation:

You have to declare which way is plus -- up or down. I will use down.

vi = - 2.85       The balloon is going up. That is the minus direction.

a = 9.81

d =   2.50 meters  distance in this case is from the object to the ground.

d = vi*t + 1/2 a t^2

-2.50 = -2.85*t + 1/2 * 9.81 * t^2

-2.50 = -2.85*t + 4.905 * t^2           transfer the left to the right.

-4.905 t^2 + 2.85*t + 2.50 = 0

Use the quadratic formula to solve for t.

It turns out that t = 1.06

Calculate the gravitational force between two bodies of masses 10kg and 55kg, if they are placed at a distance of 2m apart. ​

Answers

Answer:

F = 9.177*10^-9N

Explanation:

Gravitational force between the two bodies is expressed as;

F = GMm/r²

Given tha

M = 55kg

m = 10kg

r = 2m

G = 6.67408 × 10-11 m³ kg-1 s-2

Substitute;

F = GMm/r²

F = 6.67408 × 10-11*55*10/2²

F = 3,670.744× 10-11/4

F = 9.177*10^-9N

A body weighing 50 N is placed on a wooden table. How much force is required to set it into motion? Coefficient of friction between the table and the body is 0.3.​

Answers

If the coefficient of static friction is 0.3, then the minimum force required to get it moving is equal in magnitude to the maximum static friction that can hold the body in place.

By Newton's second law,

• the net vertical force is 0, since the body doesn't move up or down, and in particular

F = n - mg = n - 50 N = 0   ==>   n = 50 N

where n is the magnitude of the normal force; and

• the net horizontal force is also 0, since static friction keeps the body from moving, with

F = F' - f = F' - µn = F' - 0.3 (50 N) = 0   ==>   F' = 15 N

where F' is the magnitude of the applied force, f is the magnitude of static friction, and µ is the friction coefficient.

prove that vector addition obeys commutative and associative laws​

Answers

the order of vector addition doesn't affect the resultant vector and grouping or order of pair doesn't effect the sum.

If the particles that make up an object begin to move quickly, their average kinetic energy _____ and the object's temperature _____. Group of answer choices

Answers

Explanation:

If the particles that make up an object begin to move quickly, their average kinetic energy increases the object's temperature rises. Group of answer choices


The Earth orbits around the sun because the gravitational force that the sun
exerts on the Earth:
O A. causes Earth's acceleration toward the sun.
O B. is very small because the sun is so far from the Earth.
O c. is smaller than the force the Earth exerts on the sun.
O D. pushes the Earth away from the sun.

Answers

Question -:

The Earth orbits around the sun because the gravitational force that the sun

exerts on the Earth:

O A. causes Earth's acceleration toward the sun.

O B. is very small because the sun is so far from the Earth.

O c. is smaller than the force the Earth exerts on the sun.

O D. pushes the Earth away from the sun.

Answer -:

O A. causes Earth's acceleration toward the sun.

I hope this helps, have a nice time ahead!

Put the steps of the scientific method in order

Answers

step 1, ask a question
step 2, do research
step 3, make a hypothesis
step 4, test your hypothesis with an experiment
step 5, analyze your data
step 6, make a conclusion

The difference between starting and ending
positions is
distance
displacement

Answers

Answer:

displacement

Explanation:

Motion can be defined as a change in the location (position) of a physical object or body with respect to a reference point.

This ultimately implies that, motion would occur as a result of a change in location (position) of an object with respect to a reference point or frame of reference i.e where it was standing before the effect of an external force.

A reference point refers to a location or physical object from which the motion (movement) of another physical object or body can be determined.

Mathematically, the motion of an object is described in terms of acceleration, time, distance, speed, velocity, position, displacement, etc.

Displacement can be defined as the change in the position of a body or an object. It is a vector quantity because it has both magnitude and direction.

This ultimately implies that, the difference between the starting and ending positions of a physical object is generally referred to as displacement

If your weight is 588N on the earth, how far should you go from the centre of the earth so that your weight will be 300N? The radius of the earth is 6400km and the value of g on the earth surface is 9.8m/s2.​

Answers

Answer:

Hmm, Well I am pretty sure the answer is 288N

Explanation:

I got the answer 288N but I am not sure if that is correct. Hope it helps! :D

A toy rabbit of mass 0.15 kg is accelerated at 8 m/s2 by an angry toddler. Calculate the force exerted on the toy rabbit.

Answers

Answer:

1.2 N

Explanation:

Given that,

Mass (m) = 0.15 kgAcceleration (a) = 8 m/s²

We are asked to calculate force exerted (F).

[tex]\longrightarrow[/tex] F = ma

[tex]\longrightarrow[/tex] F = (0.15 × 8) N

[tex]\longrightarrow[/tex] F = 1.2 N

An unstrained horizontal spring has a length of 0.40 m and a spring constant of 340 N/m. Two small charged objects are attached to this spring, one at each end. The charges on the objects have equal magnitudes. Because of these charges, the spring stretches by 0.033 m relative to its unstrained length. Determine (a) the possible algebraic signs and (b) the magnitude of the charges.

Answers

Answer:

(a) Both the charges are positive or negative.

(b) Teh value of each charge is 1.53 x 10^-5 C.

Explanation:

Spring constant, K = 340 N/m

Natural length, L = 0.4 m

stretch, y = 0.033 m

(a) Let the charge on each sphere is q and they repel each other so the nature of charge of either sphere may be both positive or both negative.  

(b) The electrostatic force is balanced by the spring force.

[tex]\frac{kq^2}{(L + y)^2}=Ky\\\\\\\frac{9\times 10^9 q^2}{(0.4 +0.033)^2} = 340\times0.033\\\\q= 1.53\times 10^{-5} C[/tex]

A stone attached to a string is whirled round in a horizontal circle with constant speed of 10m/s .Calculate the difference in the velocity with the stone is at
I) opposite ends of a diameter
Ii) in two positions A and B where angle AOB is 90° & O is the centre of the circle ​

Answers

Answer:

Stop going on peoples pages and  answering random things kid, get a life

Learn to  solve  problems instead

Explanation:

I answered this because this kid just goes on random pages, and answers incorrectly for points. Check this egirl wannabe's profile

What is the dependent variable in this
experiment?
DONE
Biologists designed an experiment to test
the effect of compost on the development
of root crops. They tested several different
crops, including carrots, potatoes, beets,
and onions. They grew most of the plants
in the greenhouse, but due to space issues,
they had to grow some outdoors. They gave
all the plants the same amount of compost.
They obtained the compost from a local
farmer and from the local hardware store.
They ran out of the farmer's compost, so
some of the plants received that compost
when the seeds were planted and other
plants got hardware store compost after
the plants had already started growing.
What is the independent variable in this
experiment?
DONE

Answers

Answer:

"the plants had already started growing."

Explanation:

I think this is the answer because the definition of a dependent variable is the variable that is being affected by the change. Since the plants had already started growing BECAUSE of "They ran out of the farmer's compost, so

some of the plants received that compost

when the seeds were planted and other

plants got hardware store compost after

the plants had already started growing."

Sorry if I am wrong, I am just a 4th grader, pls don't hate on me, I am just trying to help :)

Answer:

It's compost

Explanation:

In case you needed the dependent variable, its the amount of plant growth

1.The distance moved by objects in a given interval of time can help us to decide which one is faster or slower. Do you agree with this statement?

Answers

Answer:

The rate of change of distance is defined as speed.

Explanation:

The speed is defined as the rate of change of distance.

Speed = distance/ time

When we know the distance and the time, we get the value of speed. So, e know that who is moving fast or slow.

hen a graph is pltted beteen the distance and time, the slope of the graph gives the value of speed. So, by checking the slopes, hoseslope ismore, the speed is more and thusit is moving faster.

So, i agree with the statement.  

Two planets are separated by a distance of 4.5x108 m. One of the planets has a mass of 2.1x1021 kg. The force of attraction between the planets is 5x1024 N. What is the mass of the other planet? (Be careful with your algebra!)

Answers

Answer:

The mass of the other planet is 7.23*10^(30) kg

Explanation:

For two objects of masses m₁ and m₂ respectively, separated by a distance r, the gravitational force between them is given by:

F = G*(m₁*m₂)/r^2

Where G = 6.67*10^(-11) m^3/(kg*s^2)

Here, we know that:

r = 4.5*10^8m

m₁ = 2.1*10^21 kg

F = 5*10^24 N

And we want to find the mass of the other planet, first, let's isolate m₂ in the force equation:

(F*r^2)/(G*m₁) = m₂

Now we can replace all the values that we know in the left side, and solve it:

m₂ =[(5*10^24 N)*( 4.5*10^8m)^2]/[6.67*10^(-11) m^3/(kg*s^2)*2.1*10^21 kg]

m₂ = 7.23*10^(30) kg

The mass of the other planet is 7.23*10^(30) kg

please help me with this question​

Answers

Answer:

1. 12 V

2a. R₁ = 4 Ω

2b. V₁ = 4 V

3a. A = 1.5 A

3b. R₂ = 4 Ω

4. Diagram is not complete

Explanation:

1. Determination of V

Current (I) = 2 A

Resistor (R) = 6 Ω

Voltage (V) =?

V = IR

V = 2 × 6

V = 12 V

2. We'll begin by calculating the equivalent resistance. This can be obtained as follow:

Voltage (V) = 12 V

Current (I) = 1 A

Equivalent resistance (R) =?

V = IR

12 = 1 × R

R = 12 Ω

a. Determination of R₁

Equivalent resistance (R) = 12 Ω

Resistor 2 (R₂) = 8 Ω

Resistor 1 (R₁) =?

R = R₁ + R₂ (series arrangement)

12 = R₁ + 8

Collect like terms

12 – 8 =

4 = R₁

R₁ = 4 Ω

b. Determination of V₁

Current (I) = 1 A

Resistor 1 (R₁) = 4 Ω

Voltage 1 (V₁) =?

V₁ = IR₁

V₁ = 1 × 4

V₁ = 4 V

3a. Determination of the current.

Since the connections are in series arrangement, the same current will flow through each resistor. Thus, the ammeter reading can be obtained as follow:

Resistor 1 (R₁) = 4 Ω

Voltage 1 (V₁) = 6 V

Current (I) =?

V₁ = IR₁

6 = 4 × I

Divide both side by 4

I = 6 / 4

I = 1.5 A

Thus, the ammeter (A) reading is 1.5 A

b. Determination of R₂

We'll begin by calculating the voltage cross R₂. This can be obtained as follow:

Total voltage (V) = 12 V

Voltage 1 (V₁) = 6 V

Voltage 2 (V₂) =?

V = V₁ + V₂ (series arrangement)

12 = 6 + V₂

Collect like terms

12 – 6 = V₂

6 = V₂

V₂ = 6 V

Finally, we shall determine R₂. This can be obtained as follow:

Voltage 2 (V₂) = 6 V

Current (I) = 1.5 A

Resistor 2 (R₂) =?

V₂ = IR₂

6 = 1.5 × R₂

Divide both side by 1.5

R₂ = 6 / 1.5

R₂ = 4 Ω

4. The diagram is not complete

1. Priya is responsible for collecting canned food along three different streets for her school's
annual Thanksgiving Food
Drive. She walks 300 m [N] along Oak Road, 500 m [E] along
Second Street, and then 150 m (S45°W) along Cross Ave. She completes the journey in 10
minutes
a. Draw a scale diagram of her trip.
b. Calculate her total distance, displacement, speed, and velocity.

Answers

Answer:

distance = 950 m

displacement = 439.2 m

speed= 1.58 m/s

velocity = 0.732 m/s

Explanation:

A = 300 m North

B = 500 m East

C = 150 m South west

Time, t = 10 minutes = 600 s

(A) The diagram is given below.

(B) Total distance = 300+ 500 + 150 = 950 m

[tex]A = 300 \widehat{j} \\\\B = 500\widehat{i}\\\\C = - 150 (cos 45 i+ sin 45 j) = - 106 \widehat{i} - 106 \widehat{j}\\\\D = A + B + C \\\\D = 394 \widehat{i} + 194 \widehat{j}\\\\D=\sqrt{394^2 +194^2} = 439.2 m[/tex]

Speed = distance / time = 950/600 = 1.58 m/s

velocity = 439.2 / 600 = 0.732 m/s

In a second order lever system the force ratio is 2.5, the load is at the distance of 0.5m from the fulcrum find distance of effort if it losses are negligible​

Answers

Answer:

1.25 m

Explanation:

From the question given above, the following data were obtained:

Force ratio = 2.5

Distance of load from the fulcrum = 0.5 m

Distance of effort =.?

The distance of the effort from the fulcrum can be obtained as illustrated below:

Force ratio = Distance of effort / Distance of load

2.5 = Distance of effort / 0.5

Cross multiply

Distance of effort = 2.5 × 0.5

Distance of effort = 1.25 m

Therefore, the distance of the effort from the fulcrum is 1.25 m

write any two difference between CGS and MKS system of measurement ?​

Answers

Answer:

MKS stands for Meter, Kilogram and second. In this system of unit mass is given in Kilogram, length in meter and time in second. ... CGS system stands for Centimeter- Gram- Second system. In CGS system, length is measured in centimeters mass is measured in grams and time is in seconds.

Astronomers observe the Small Magellanic Cloud (SMC), a not very dense, rather small galaxy near us. They notice that even those stars that formed recently have relatively few heavier elements (when compared to such recent stars in our Milky Way.) What is the likely explanation for this deficiency

Answers

Answer:

The reason it has few heavier elements is due to the fact that it's stars are widely spaced and this implies that it's stars have very low rate of formation and termination.

Explanation:

The Small Magellanic Cloud, is basically a very tiny galaxy located near the Milky Way. Although it's tiny, it's diameter is approximately 7,000 light-years while it also contains over hundred million stars which are widely spaced.

Now, the reason it has few heavier elements is due to the fact that it's stars are widely spaced and this implies that it's stars have very low rate of formation and termination.

three condensers are connected in series across a 150 volt supply, the voltages across them are 40,50 and 60 volts respectively, and the charge on each condenser is 6×10^-8 c.calculate (a) the capacitance of each condenser (b)the effective capacitance of the combination

Answers

Answer:

(a) 1.5 nF, 1.2 nF, 1 nF

(b) 0.4 nF

Explanation:

V = 150 V

V' = 40 V, V'' = 50 V, V''' = 60 V, q = 6 x 10^-8 C

(a) C' = q/V' = 6 x 10^-8 / 40  = 1.5 x 10^-9  F

C'' = q/V'' = 6 x 10^-8 / 50 = 1.2 x 10^-9 F

C''' = q/V''' = 6 x 10^-8 / 60 = 1 x 10^-9 F

(b) The effective capacitance is

[tex]\frac{1}{C}=\frac{1}{C'}+\frac{1}{C''}+\frac{1}{C'''}\\\\\frac{1}{C}=\frac{10^9}{1.5}+\frac{10^9}{1.2}+\frac{10^9}{1}\\\\C = 0.4\times 10^{-9} F[/tex]  

please help me with my question due tomorrow morning,

Answers

Answer:

D)7 1/2 or 15/2

Explanation:

Let's calculate Combined resistance of the parallel first

1/Rt= 1/2+1/6=4/6

Rt=6/4 which is also equal with 3/2

Now let's add it with the series one

Rt= 6+3/2

=15/2 And when we put that un a mixed fraction 7 1/2

Define couple and give 2 examples

Answers

Answer:

Two equal and opposite parallel forces not acting along the same line, form a couple. A couple is always needed to produce the rotation.

For example, turning a key in a lock and turning a steering wheel.

A couple consists of two parallel forces that are equal in magnitude, opposite in sense and do not share a line of action. ... For example, the forces that two hands apply to turn a steering wheel are often (or should be) a couple. Each hand grips the wheel at points on opposite sides of the shaft.

A ball of mass 0.3 kg is released from rest at a height of 8 m. How fast is it going when it hits the ground? (Gravity being equal to 9.8)

Answers

Answer:

Explanation:

Mass doesn't matter here because when something is falling, gravity plays fairly; an elephant falls at the same rate of acceleration as does a feather. What DOES matter is everything pertinent to the y-dimension of free-fall:

a = -9.8 m/s/s

v₀ = 0 (since the ball was held before it was dropped)

v = ??

Δx = -8 m (negative because the ball drops this far below the point from which it was released).

Putting all this together in one equation:

v² = v₀² + 2aΔx and filling in this equation:

v² = (0)² + 2(-9.8)(-8) and

v² = 156.8 so

v = 12.5 which rounds to 13 if you're using 2 sig figs, and rounds to 10 if you're only using 1 (which you should be, according to the way the numbers have been given in this problem)

A screw Jack whose pitch is 2mm is used to raise a bus of mass 900kg through height of 20cm. The length of the Tommy of the Tommy of the jack is 40cm. Calculate the velocity ratio of the machine

Answers

R= 40cm —> R= 0.4 m

P= 2mm —> P= 0.002 m

[tex]V.R = \frac{2πR}{p} = \frac{2 \times 3.14 \times 0.4}{0.002} = 1256[/tex]

I think this is the answer

I hope I helped you

Good luck ^_^

A car moves with the speed of 40 km/hr for the first half and 60 km/hr
for Second half distance "What is the average distance of cars.​

Answers

Answer:

50 km/h

Explanation:

[tex](40 + 60) / 2[/tex]

-> [tex]50[/tex] (km/h)

A train is travelling at 50 m s−1 when the driver applies the brakes and gives the train a constant deceleration of magnitude 0.50 m s−2 for 100 s. Describe what happens to the train. Calculate the distance travelled

Answers

Answer:

The strain will come to rest after traveling some distance.

distance traveled = 2500 m

Explanation:

The strain will come to rest after traveling some distance.

Applying,

s = ut+at²/2................... Equation 1

Given: u = initial velocity, a = deceleration, t = time, s = distance

From the question,

Given: u = 50 m/s, t = 100s, a = -0.5 m/s²(deceleration)

Substitute these values into equation 1

s = 50(100)+(-0.5)(100²)/2

s = 5000-2500

s = 2500 m

Hence the distance traveled is 2500 m

Answer the question plz

Answers

Answer:

b and d

Explanation:

Other Questions
UHM THERE IS MORE QUESTIONS OR I WILL BE PUNISH IN THE BIBLE SIMION WHAT IS ANOTHER NAME FOR SIMON? So for this problem I got the scientific notation however I can not seem to figure out the standard notation. I thought it is the same answer but it is not. Can someone please help me out here please? Read, and choose the option with the best word or words to complete the sentence.________ usa la calculadora y trabaja con nmeros en su oficina. La contable La guardia de seguridad La recolectora de basura La soldado When stagflation occurs, what happens to American trade? A. It increases rapidly. B. It decreases rapidly. C. It completely stops. D. It leads to a global depression. Please help :((((((((((((((((((((((((( 30 points if helped, question in the picture TIMED PLEASE HELP ASAPSelect ALL of the following that the article says are negative consequences of the "McDonaldization" of society.IrrationalityDisenchantmentDehumanization Surface area of a cuboid is 384 work out the volume Write the equation of the graph y= list four reasons why the poll tax ordinance of 1862 was introduced Which of the following means "make"? A. -lan B. -or C. -fy D. -ent A psychiatrist performing a mental exam shows a list of 10 unrelated images to the patient and asks the patient to memorize them. The exam continues and a few minutes later the psychiatrist requests that the patient describe as many images as he can recall. If most of the remembered images come from the beginning and end of the list, this is an example of: expand and simplify (x-2)(x+5)(2x-1) What is socialization? Write in your own words. helpppppppppppppppppp a train leaves Westchester at 6:30. What time should it arrive at Middlewich NO LINKS OR ANSWERING WHAT YOU DON'T KNOW?1. Suppose y varies inversely with x, and y = 25 when x = 1/5. What is the value of y when x = 5?a. 15b. 5c. 25d. 12. Suppose y varies inversely with x, and y = a when x = a^2. What inverse variation equation related x and y?a. y = a^2/xb. y = a^3/xc. y= a^3xd. y = ax3. Suppose y varies inversely with x, and y = 3 when x = 1/3. What is the inverse variation equation that relates x and y?a. y = 1/xb. y =xc. y = 3xd. y = 3/x One number is 6 times a second number. The sum of the two numbers is 56. Find the numbersOne number is 6 times a second number. The sum of the two numbers is 56. Find the numbers If the mirror reflection coefficients for a laser resonator of length 5 m are 98.5% and 60%, and there are no losses, determine the cavity threshold gain What is the main conflict in the the gift of the magi?