Answer:
true 1Ay 2D
Explanation:
1) In this exercise you are asked to investigate which statements are true
A) True. The friction force opposes the movement caused by the external force,
B) False. Mantuano in the opposite direction force
C) False. The static and scientific friction force act in the same direction, since the second appears when the movement does not start and the static friction decreases.
D) Fale the static and kinetic friction forces act in the same direction
2) How to overcome friction on a ramp
A) False. If the texture of the surface becomes rough, the friction force increases
B) False. Pressing the brick against the surface increases the normal and as the friction is proportional to the normal, it also increases
C) False. By lowering the table the weight component in the friction direction decreases
D) True. When lifting the board, the weight component increases and therefore can become greater than the friction
Wx-fr = ma
W sin tea - my mg cos tea = m a
As it increases, the sine increases and the cosine decreases.
which solid state component allows a mobile phone to store data even if the battery is removed
Answer:
Capacitor
Explanation:
Capacitor ; A capacitor is a passive two-terminal electrical component that can store energy in an electric field electrostatically. It works as a small rechargeable battery that stores electricity. However, unlike a battery, it can charge and discharge in the split of a second. Capacitors are widely used to build different types of electronic circuits.
What would most likely cause an accident if worn in a lab? short sleeves short hair long jewelry long pants
Answer:
Long jewelry
Explanation:
What is the magnitude of displacement if a person goes 290 m east followed by 150 m west?
Answer:140 m
Explanation:
Displacement = 290-150= 140 m
Two students are watching a person riding a skateboard up and down a ramp. Each student shares what they think about the energy of the skateboarder as they ride up and down the ramp. Elisa: I think the skateboarder has the more total energy at the top bottom of the ramp than the bottom of the ramp. Raymond: I think the skateboarder has the same total energy at all points on the ramp.
Answer:
Explanation:
We know that , If the frictional force on a system is zero , then the total energy of a system will be conserved.
By using energy conservation
KE₁ + U₁ = KE₂ + U₂
KE₁=Kinetic energy at location 1
U₁ =Potential energy at location 1
KE₂=Kinetic energy at location 2
U₂=Potential energy at location 2
Therefore, Raymond is thinking in a right way.
Why rolling friction less than sliding friction
The force of friction depends on the area of contact between the two surfaces. As the area of contact is less in the case of rolling than in the case of sliding that's why rolling friction is less than the sliding friction. More the contact area more the friction.
A 8.0-cm long solenoid has 2000 turns of wire and carries a current of 5.0-A. Calculate the strength of the magnetic field at the center of the solenoid in teslas.
Answer:
B = 0.157 T
Explanation:
Given that,
Length of the solenoid, l = 8 cm = 0.08 m
Number of turns in the wire, N = 2000
Current, I = 5 A
We need to find the strength of the magnetic field at the center of the solenoid. It is given by the formula as follows :
[tex]N=\mu_o nI[/tex], N is number of turns per unit length of solenoid.
So,
[tex]B=4\pi \times 10^{-7}\times \dfrac{2000}{0.08}\times 5\\\\=0.157\ T[/tex]
So, the magnetic field at the center of the solenoid is 0.157 T.
Contrast the sizes between that of a red blood cell against a single motor neuron.
Answer:
Explanation:The average human adult has more than 5 liters (6 quarts) of blood in his or her body. Blood carries oxygen and nutrients to living cells and takes away their waste products. It also delivers immune cells to fight infections and contains platelets that can form a plug in a damaged blood vessel to prevent blood loss
24. Compare and contrast the 'Big Bang Theory' with the 'Creation Model for the origin of the
universe.
*** Be sure to include similarities and differences between the 2 theories and information on
how and why these theories have developed over time. Use the Ven diagram on the next
page to assist you.
What was the initial velocity of a robot that took 5 m to get to final velocity of 19 m/s at a rate of 3 m/s/s?
Answer:
4m/s
v=u+at
19=u+3*5
u=4m/s
Potential energy is the energy of
Answer:
potential energy is the energy that is stored in an object due to its position relative to some zero position. An object possesses gravitational potential energy if it is positioned at a height above (or below) the zero height.
a ballon filled with nitrogen gas has a small leak. Another ballon filled with hydrogen gas has an identical leak. How much faster will the hydrogen balloon deflate
Answer:
4 times that of nitrogen gas, N2.
Explanation:
Let R1 be the rate of diffusion of nitrogen gas, N2.
Let R2 be the rate of diffusion of Hydrogen gas, H2.
Let M1 be the molar mass N2
Let M2 be the molar mass of H2.
Next, we shall determine the molar mass of N2 and H2.
This is illustrated below below:
Molar mass of N2 (M1) = 2 x 14 = 28 g/mol
Molar mass of H2 (M2) = 2 x 1 = 2 g/mol
Finally, we shall determine the rate of diffusion of Hydrogen gas, H2 as follow:
R1/R2 = √(M2/M1)
M1 = 28
M2 = 2
R1/R2 = √(M2/M1)
R1/R2 = √(2/28)
R1/R2 = √(1/14)
R1/R2 = 0.27
Cross multiply
R1 = R2 × 0.27
Divide both side by 0.27
R2 = R1/0.27
R2 = R1 × 1/0.27
R2 = R1 × 4
R2 = 4R1
Therefore, the rate of diffusion of H2 (R2) is 4 times that of N2 (R1)
what are the abuses limitation and benefits of science (pls tell at least 5 each)
Answer: The generation of electricity using fossil fuels.e.g can lead to pollution which cause harm to human beings and environment.
At some times science and technology have been misused or abused by human beings.An example of abuse is the invention of and use of deadly weapons which are harmful to us and environment.
Explanation:
A physics student throws a ball straight up. The student catches the ball in exactly the same place from which it was released. The ball’s time of flight is T, and its maximum height above its release point is H. Neglect air resistance and assume up is the positive direction. Find the ball’s average velocity during the second half of its trip. (Hint: Your answer should only have the variables H and T in it.)
Answer:
The correct answer is H ÷ ¹/₂T
Explanation:
The formula for velocity is distance covered ÷ time.
Neglecting air resistance;
If the ball's time of overall time flight is T, the time it will take for the second half/return trip is ¹/₂T.
If the ball's maximum height above its released point is H, the height will also be the distance it covered for the second part of the trip since the student caught the ball in the exact same place the ball was thrown. Hence, the distance for the second half of the trip will be H.
Since velocity = distance/time
The average velocity during the second half of the trip will be = H ÷ ¹/₂T
Engine of vehicles are manufacturers on the principle of _____
Explanation:
As the principle, a mixture gas of the fuel and the air is compressed in the cylinder at first and the gas exploded by use of an ignition plug and generate the output power
Explanation:
Engine of vehicles are manufacturers on the principle of internal combustion engine
convert 0.000238 m to cm
Answer:
0.0238 centimetre
Explanation:
multiply the length value by 100
What does this student most likely need to do in order to be better prepared to stay safe in a lab?
take off the goggles
change into lighter shoes
wear different clothing
tie back her hair
she needs to tie back her hair
What volume will be occupied by 20g of Copper if the density of Copper is 9.1g/ml?
Answer:
The volume of copper is 2.198 ml
Explanation:
Given;
mass of copper, m = 20 g
density of copper, ρ = 9.1 g/ml
Density is given by;
Density = mass / volume
Volume = mass / density
Volume = (20 g) / (9.1 g/ml)
Volume = 2.198 ml
Therefore, the volume of copper is 2.198 ml
If you drive 125 km in 2 hours, what is your average speed
Formula: s = d/t
s = speed
d = distance
t = time
Solve using the values we were given.
s = 125/2
S = 62.5km per hour
Best of Luck!
Tech A says that total resistance goes up as more parallel paths are added. Tech B says that total amperage goes up as more parallel paths are added. Who is correct
Answer: Tech B says that total amperage goes up as more parallel paths are added. Who is correct
Explanation: Tech B is correct, because amperage has been known to go up through when more parallel paths are added to a circuit. this is so because when more resistors are introduced in parallel to a circuit, the resulting resistance of the circuit would decrease, this increases the total current of the circuit. as a result, when more resistors are added in parallel what you get is a change in the direction of flow which is equal to providing more branches which charge can flow through.
zeros are always considered significant digits when they are to the left of the decimal point True or False
Answer:
false
Explanation:
because they does'nt Work for anything, are like they are not there
Answer:
False
Explanation:
The rules for significant figures are:
Non-zero digits are always significant.Zeros between significant digits are also significant.Trailing zeros are significant only after a decimal point.A zero before a decimal point is only significant if there's a non-zero digit before it.
For example, in the number 10.5, the zero is significant, because it is between significant digits.
But in the number 0.5, the zero is not significant.
The moon Umbriel orbits Uranus (mass = 8.68 x 1025 kg) at a distance of 2.66 x 108 m. What is Umbriel's orbital speed?
Answer:
the orbital speed of umbriel is 16,800 km/h
Explanation:
The computation of the orbital speed is shown below
According to the question the Data provided in the question
Uranus mass = 8.68 × 10^25 kg
Distance = 2.66 × 10^8 m
Based on the above information, the orbital speed of Umbriel is
[tex]V = \sqrt{\frac{GM}{R} } \\\\ = \sqrt{\frac{((6.673e-11)(8.68e25)}{2.66e8} }[/tex]
V = 4666 m/s
= 16,800 km/h
Hence, the orbital speed of umbriel is 16,800 km/h
Therefore it can be calculated by applying the above formula
Answer: 4665
Explanation: I got it right after on acellus
why a flying airplane has more kin etic energy than a flying insect
Explanation:
Airplanes have more kinetic energy because their bigger. A bug is a living thing well a airplane is not so it (the airplane) has all these machines and engines to make it go faster.
a cannonball is fired with a speed of 76 m/s from the top of a cliff. It strikes the plane below with a speed of 89 m/s. if we neglect air friction, how high is the cliff
Assuming the cannonball is fired horizontally, its horizontal velocity stays at a constant 76 m/s. At the point it hits the ground, it has a speed of 89 m/s, so if its vertical velocity at that moment is [tex]v_y[/tex], we have
[tex]89\dfrac{\rm m}{\rm s}=\sqrt{\left(76\dfrac{\rm m}{\rm s}\right)^2+{v_y}^2}\implies{v_y}^2\approx2145\dfrac{\mathrm m^2}{\mathrm s^2}[/tex]
(taking the negative square root because we take the downward direction to be negative)
Recall that
[tex]{v_f}^2-{v_i}^2=2a\Delta x[/tex]
where [tex]v_i[/tex] and [tex]v_f[/tex] are the initial and final velocities, respectively; [tex]a[/tex] is the acceleration; and [tex]\Delta x[/tex] is the change in position of a body. In the cannonball's case, it starts with 0 vertical velocity and is subject to a downward acceleration with magnitude [tex]g=9.80\frac{\rm m}{\mathrm s^2}[/tex]. So we have
[tex]2145\dfrac{\mathrm m^2}{\mathrm s^2}-0=-2g\Delta y\implies\Delta y\approx-109.44\,\mathrm m[/tex]
(which is negative because we take the cannonball's starting position at the top of the cliff to be the origin) so the cliff is about 109 m high.
When two bodies of different temperatures are placed together and left for sometime, Both of them attain the same temperature.
(Heat flows from a body of Higher temperature to a body of lower temperature)
Now after they attain the same temperature will there be
No transfer of heat between them
Or
Will there be an equal amount of heat lost and gained by both the bodies?
My answer would be an equal amount of heat is lost and gained by both the bodies
You can't exactly say that there is no heat transfer just because equal amount is lost and gained by the bodies right?
My text book says that there is NO transfer of heat once both the bodies attain same temperature
hi olivia hope this helps you
12. Prove that v' = u? + 2as.
Prove that v² = u² + 2as .
Solution:-From first equation of motion,
v = u + at
=> at = v - u
=> t = v - u / a
From the second equation of motion, we have
s = ut + 1/2at²
Putting the value of t in above equation , we get:
s = u ( v - u /a ) + 1/2 a ( v - u/a )²
s = uv - u² / a + a( v² + u² - 2uv / 2a²)
s = uv - u² / a + v² + u² - 2uv / 2a
s = 2uv - 2u² + v² + u² - 2uv / 2a
2as = v² - u²
Answer:
[tex] \boxed{ \boxed{ \orange{ \sf{see \: below}}}} [/tex]
Explanation:
[tex] { \underline{ \underline \bold{ \sf{ \blue{ {question \: }}}}}}[/tex]
[tex] \sf{ \bold{ \underline{ \: prove \: that \: {v}^{2} = {u}^{2} + 2as}}}[/tex]
[tex] \underline{ \underline{ { \bold{ \sf{ \purple{solution} }}}}}[/tex]
Let us assume a body moving with an initial velocity ' u '. Let it's final velocity be 'v' after a time 't' and the distance travelled by the body be 's'. We already have ,
[tex] \sf{v = u + at}[/tex] ⇒first equation of motion ( i )
[tex] \sf{s = \frac{u + v}{2} \times t}[/tex] ⇒second equation of motion ( ii )
Putting the value of t from ( i ) in the equation ( ii )
{ v = u + at
or , at = v - u
or, t = v-u / a }
[tex] \sf{s = \frac{u + v}{2} \times \frac{v - u}{a} }[/tex]
[tex] \sf{or \: s = \frac{ {v}^{2} - {u}^{2} }{2a} }[/tex]
[tex] \sf{or \: 2as = {v}^{2} - {u}^{2} }[/tex]
[tex] \sf{ \boxed{ \bold{ \: ∴ \: \: \: {v}^{2} = {u}^{2} + 2as}}}[/tex] ⇒ forth equation of motion
Hope I helped!
Best regards!!
A 12cm candle is placed 6cm from a converging lens with a focal length of 15cm. What is the height of the image of the candle? Show all calculations and use SALT to describe the image.
Answer:
The height of the image of the candle is 20 cm.
Explanation:
Given that,
Size of the candle, h = 12 cm
Object distance from the candle, u = -6 cm
Focal length of converging lens, f = 15 cm
To find,
The height of the image of the candle.
Solution,
Firstly, we will find the image distance of the candle. Let it is equal to v. Using lens formula to find the image distance.
[tex]\dfrac{1}{f}=\dfrac{1}{v}-\dfrac{1}{u}[/tex]
v is image distance
[tex]\dfrac{1}{f}=\dfrac{1}{v}-\dfrac{1}{u}\\\\\dfrac{1}{v}=\dfrac{1}{f}+\dfrac{1}{u}\\\\\dfrac{1}{v}=\dfrac{1}{15}+\dfrac{1}{(-6)}\\\\v=-10\ cm[/tex]
If h' is the height of the image. Magnification is given by :
[tex]m=\dfrac{h'}{h}=\dfrac{v}{u}[/tex]
[tex]h'=\dfrac{vh}{u}\\\\h'=\dfrac{-10\times 12}{-6}\\\\h'=20\ cm[/tex]
So, the height of the image of the candle is 20 cm.
A wrench weighs 5.24 N on Earth. When it is taken to the Moon, where g = 1.60 m / s? how much does it weigh? (Hint: Its mass does not change.) (Unit = N)
Answer:
The weight of the wrench on the Moon is approximately 0.8555 N
Explanation:
On Earth, the acceleration of gravity at sea level is 9.8 m/s^2
then if the wrench weights 5.24 N that means that its mass according to Newton's second law is:
[tex]F = m \, a\\m=\frac{F}{a} \\m=\frac{5.24}{9.8} \, kg\\m=0.5347[/tex]
Now we can use the wrench's mass to find its weight on the Moon, knowing that the acceleration due to gravity there is 1.6 m/s^2:
[tex]W=m\,g\\W=(0.5347) \,(1.6) \,N\\W=0.8555\,\,N[/tex]
Answer:
Explanation:
0.8555
Suppose all of the apples have a mass of 0.10 kg. If apple (A) is sitting on the ground, what is its potential energy?
Answer:
The answer is C 0.0
Explanation:
Because its sitting still on the ground.
Answer:
0.0j
Explanation:
What displacement do I have if I travel 10 m E, then 6 m W, then 12 m E? A. 16 m E B. 28 m E C. 28 m D. 16 m
Answer:
16m E
Explanation:
displacement=10m E-6m W+12m E=16m E
A metal sphere of radius 3cm made of brass is heated from
30°C to 100°C , Calculate the initial and final volume of the
metal sphere (Iinear expansivity of brass =0.000019k-¹ and volume of sphere =⁴/3 πr³
Answer:
Let:
r= radius= 3cm= 0.03m
∅1= initial temperature= 30°C
∅2= final temperature= 100°C
∆∅= change in temperature= ∅2 - ∅1= 70°C
L.E.= linear expansivity= 0.000019k^-1
¥= 3L.E.= volume expansivity= 3(0.000019)= 0.000057k^-1
The initial volume of the metal sphere= 4/3(πr³)
= 4/3(π×0.03³)
= 4(π×0.03²×0.01)
= 4(3.142×0.0003×0.01)
= 4(0.000009426)
= 0.000037704
= 3.7704 × 10^-5m³
¥= V2 - V1/V1∆∅
V2= ¥V1∆∅ + V1
= (1.5044 × 10^-7) + (3.7704×10^-5)
= 0.00003785
= 3.785 × 10^-5m³
Therefore, the initial and final volume of the metre sphere are 3.7704 × 10^-5 and 3.785 × 10^-5 respectively.