Given :
Initial speed, u = 0 m/s.
Final speed, v = 9 m/s.
Time taken to reach that speed, t = 2 sec.
To Find :
The acceleration of the athlete.
Solution :
We know, in uniform acceleration motion :
[tex]v= u+at\\\\a = \dfrac{v-u}{t}\\\\a = \dfrac{9-0}{2}\ m/s\\\\a = 4.5 \ m/s^2[/tex]
Therefore, acceleration of the athlete is 4.5 m/s².
what is rhe average velocity od a baseball dropped from rest that falls for 2 seconds?
Answer:
19.6m/s
Explanation:
Given parameters:
Initial velocity = 0m/s
Time = 2s
Unknown:
Average velocity = ?
Solution:
We can use the final velocity of the ball before landing to determines its average velocity ;
Using;
v = u + gt
v is the final velocity
u is the initial velocity
g is the acceleration due to gravity
t is the time
v = 0 + 9.8 x 2 = 19.6m/s
On a circular racetrack with a radius of 3.23 m, a certain road car set a speed record of 3.72
m/s. If the car had a mass of 250 kg, what was the net force acting on it?
Answer:
F = 1071.08 N
Explanation:
Given that,
The radius of the circular track, r = 3.23 m
Speed of the car, v = 3.72 m/s
The mass of the car, m = 250 kg
We need to find the net force acting on it. The centripetal force will act on it and it is given by the relation as follows :
[tex]F=\dfrac{mv^2}{r}\\\\F=\dfrac{250\times (3.72)^2}{3.23}\\\\F=1071.08\ N[/tex]
So, the net force acting on the car is 1071.08 N.
The five general principles from the APA are meant to __________. A. be enforceable rules B. be posted in every office C. guide and inspire good conduct D. stand up in court Please select the best answer from the choices provided
The five general principles from the APA are meant to: C. Guide and inspire good conduct.
During which season of the year will your nails grow most quickly?
summer
spring
fall
winter
Answer:
summer
Explanation:
mmmeeeee,I'M BEING TIMED
Answer:
D) See the explanation below.
Explanation:
Heat transfer is always given from a body of higher temperature to a lower temperature. In this way the heat from the boiling water is transferred to the ice bars and the energy of the phase change from solid to liquid from the ice is transferred to the environment
A missile is launched upward with a speed that is half the escape speed. What height (in radii of Earth) will it reach?
Answer:
The height (h) will be: [tex]\frac{3}{4}R =h[/tex]
Explanation:
The scape speed equation is given by:
[tex]v_{scape}=\sqrt{\frac{2GM}{R}}[/tex]
Now, the speed of the missile is
[tex]v_{missile}=\frac{1}{2}v_{scape}[/tex]
[tex]v_{scape}=\frac{1}{2}\sqrt{\frac{2GM}{R}}[/tex]
Using the conservation of energy, we can find the maximu height of the missile.
[tex]E_{i}=E_{f}[/tex]
[tex]\frac{1}{2}mv_{scape}^{2}-mgR =-mgh[/tex]
[tex]\frac{1}{2}\frac{2GM}{4R}-gR =-gh[/tex]
[tex]\frac{GM}{4R}-gR =gh[/tex]
Let's recall that g = GM/R², using the equivalence principle. When R is the radius of the earth and M is the mass of the earth.
[tex]\frac{1}{4}gR-gR =-gh[/tex]
[tex]\frac{1}{4}R-R =-h[/tex]
Therefore the height (h) will be:
[tex]\frac{3}{4}R =h[/tex]
I hope it helps you!
An electric motor spins at 1000 rpm and is slowing down at a rate of 10 t rad/s2 ; where t is measured in seconds. (a) If the motor radius is 7.165 cm, what is the tangential component of acceleration at the edge of the motor at t = 1.5 seconds? (b) How long will it take, in seconds, to decrease its angular velocity by 75%?
Answer:
a) The tangential component of acceleration at the edge of the motor at [tex]t = 1.5\,s[/tex] is -1.075 meters per square second.
b) The electric motor will take approximately 3.963 seconds to decrease its angular velocity by 75 %.
Explanation:
The angular aceleration of the electric motor ([tex]\alpha[/tex]), measured in radians per square second, as a function of time ([tex]t[/tex]), measured in seconds, is determined by the following formula:
[tex]\alpha = -10\cdot t\,\left[\frac{rad}{s^{2}} \right][/tex] (1)
The function for the angular velocity of the electric motor ([tex]\omega[/tex]), measured in radians per second, is found by integration:
[tex]\omega = \omega_{o} - 5\cdot t^{2}\,\left[\frac{rad}{s} \right][/tex] (2)
Where [tex]\omega_{o}[/tex] is the initial angular velocity, measured in radians per second.
a) The tangential component of aceleration ([tex]a_{t}[/tex]), measured in meters per square second, is defined by the following formula:
[tex]a_{t} = R\cdot \alpha[/tex] (3)
Where [tex]R[/tex] is the radius of the electric motor, measured in meters.
If we know that [tex]R = 7.165\times 10^{-2}\,m[/tex], [tex]\alpha = 10\cdot t[/tex] and [tex]t = 1.5\,s[/tex], then the tangential component of the acceleration at the edge of the motor is:
[tex]a_{t} = (7.165\times 10^{-2}\,m)\cdot (-10)\cdot (1.5\,s)[/tex]
[tex]a_{t} = -1.075\, \frac{m}{s^{2}}[/tex]
The tangential component of acceleration at the edge of the motor at [tex]t = 1.5\,s[/tex] is -1.075 meters per square second.
b) If we know that [tex]\omega_{o} = 104.720\,\frac{rad}{s}[/tex] and [tex]\omega = 26.180\,\frac{rad}{s}[/tex], then the time needed is:
[tex]26.180\,\frac{rad}{s} = 104.720\,\frac{rad}{s}-5\cdot t^{2}[/tex]
[tex]5\cdot t^{2} = 104.720\,\frac{rad}{s}-26.180\,\frac{rad}{s}[/tex]
[tex]t^{2} = \frac{104.720\,\frac{rad}{s}-26.180\,\frac{rad}{s} }{5}[/tex]
[tex]t = \sqrt{\frac{104.720\,\frac{rad}{s}-26.180\,\frac{rad}{s} }{5} }[/tex]
[tex]t \approx 3.963\,s[/tex]
The electric motor will take approximately 3.963 seconds to decrease its angular velocity by 75 %.
What is the Pythagorean Theorem used to find and what must you have to use it?
a. magnitude, fight triangle
b. direction, right triangle
c. magnitude, parallelogram
d. direction, parallelogram
Answer:
A
Explanation:
A particle moves in a circle 1.50 m in radius. Through what angle in radians does it rotate if it moves through an arc length of 2.50 m
Answer:
95.7 degrees
Explanation:
The angle through which the particle rotate in radians is 1.667 rad.
Given the following data:
Radius of circle = 1.50 meterArc length = 2.50 meters.To determine the angle through which the particle rotate in radians:
Mathematically, the angular displacement or arc length in circular motion is given by the formula:
[tex]S=r\theta[/tex]
Where:
S is the angular displacement or arc length.r is the radius.[tex]\theta[/tex] is the angle measured in radians.Making [tex]\theta[/tex] the subject of formula, we have:
[tex]\theta=\frac{S}{r}[/tex]
Substituting the given parameters into the formula, we have;
[tex]\theta = \frac{2.50}{1.50} \\\\\theta =1.667 \;rad[/tex]
Read more: https://brainly.com/question/8898885
Experiencing a "jump scare" in a frightening movie most immediately activates your:
somatic nervous system.
sympathetic nervous system.
parasympathetic nervous system.
decentralized nervous system.
Answer:
Somatic I think
Explanation:
Answer:Sympathetic nervous system
Explanation:
A birthmark is generally a:
macule.
excoriation.
pustule.
bullae.
Answer:
macule
Explanation:
its aa flat round areausually distingurished from its surroundung skin by its changed in color. smaller than 1cm am small hemorrhage spot.
How much power is produced by flashlight that has a voltage of 12 volts and a current of 6.5 x 10^-2 amps? A. 0.78 watts B. 78 watts C. 190 watts D. 0.0054 watts E. 1.9 watts
Answer:
the powar produced is 0.7 watts
The alarm at a fire station rings and a 87.5-kg fireman, starting from rest, slides down a pole to the floor below (a distance of 4.10 m). Just before landing, his speed is 1.75 m/s. What is the magnitude of the kinetic frictional force exerted on the fireman as he slides down the pole?
Answer:
[tex]F_f=840N[/tex]
Explanation:
From the question we are told that
Weight of fireman [tex]W_f= 87.5kg[/tex]
Pole distance [tex]D=4.10m[/tex]
Final speed is [tex]V_f 1.75m/s[/tex]
Generally the equation for velocity is mathematically represented as
[tex]v^2 = v_0^2 + 2 a d[/tex]
Therefore Acceleration a
[tex]a'= v^2 / 2 d[/tex]
[tex]a'= 0.21m/s^2[/tex]
Generally the equation for Frictional force [tex]F_f[/tex] is mathematically given as
[tex]F_f=m*a[/tex]
[tex]F_f=m*(g-0.21)[/tex]
[tex]F_f=87.5*(9.81-0.21)[/tex]
Therefore
[tex]F_f=840N[/tex]
If you live in the southern hemisphere, what season would you be experiencing in position C this diagram?
A)
Fall
B)
Summer
C)
Winter
D)
Spring
Which is another way of saying the law of conservation of mass?
The mass of the reactants always equals the mass of the products.
Matter cannot be created or destroyed.
the law of conservation of matter
all of the above
Answer:is there a 1 2 3 4 answer?
Explanation:
A horse is working steadily, providing 750 W of output power. How much food energy does the horse need to work for 1 hour, to the nearest MJ
Answer:
Under assumption that all food energy that needs the horse is transformed into work, then the horse needs approximately 3 megajoules of food energy to work for 1 hour.
Explanation:
Since horse is working steadily, the power experimented by the horse ([tex]\dot W[/tex]), measured in watts, is at constant rate. Then, the work needed by the horse ([tex]W[/tex]), measured in joules, is equal to that power multiplied by time ([tex]\Delta t[/tex]), measured in seconds. That is:
[tex]W = \dot W\cdot \Delta t[/tex] (1)
If we know that [tex]\dot W = 750\,W[/tex] and [tex]\Delta t = 3600\,s[/tex], then the work needed for the horse is:
[tex]W = (750\,W)\cdot (3600\,s)[/tex]
[tex]W = 2.7\times 10^{6}\,J[/tex]
[tex]W = 2.7\,MJ[/tex]
Under assumption that all food energy that needs the horse is transformed into work, then the horse needs approximately 3 megajoules of food energy to work for 1 hour.
Three tension forces OA, OB and OC are equal in magnitude and magnitude of their summation is 200 N. What is the magnitude of each force
Answer:
The magnitude of each force is 66.67 N
Explanation:
Given that the magnitude of the tension forces are equal. Let the magnitude of the tension forces be represented by x, such that;
|OA| = |OB| = |OC| = x
Since their summation = 200 N, then;
|OA| + |OB| + |OC| = 200
This implies that;
x + x + x = 200
3x = 200
x = [tex]\frac{200}{3}[/tex]
= 66.6667
x = 66.67 N
Therefore, the magnitude of each tension force is approximately 66.67 N
Sound waves are simultaneously interpreted through air (going through the external,
middle, then inner ear) and through the bone in the inner ear, stimulating the
acoustic nerve.
True
False
Answer:
its true
Explanation:
i took it
A projectile is launched at an angle of 60° from the horizontal and at a velocity of
12.0 m/s. What is the horizontal velocity of the projectile? *
Answer:
60*12.0= 720 = v/60 * 12.0 squared which is 1,728
Explanation:
Horizontal velocity component: Vx = V * cos(α)
The horizontal velocity of the projectile is 6.0m/s
If a projectile is launched at an angle from the horizontal and at a velocity v, the horizontal velocity of the projectile is expressed as:
[tex]v_x =vcos \theta[/tex]
Given the following parameters
v = 12.0m/s
[tex]\theta=60^0[/tex]
Substitute the given parameters into the formula to have:
[tex]v_x=12.0cos60\\v_x=12.0(0.5)\\v_x=6.0m/s\\[/tex]
Hence the horizontal velocity of the projectile is 6.0m/s
Learn more here: https://brainly.com/question/23916021
Match each disease to the correct pathogen type
Protist:
Virus:
Fungus:
A) AIDS
B) Histoplasmosis
C) Amoebic dysentery
Answer:
Protist: C) Amoebic dysentery
Virus: A) AIDS
Fungus: B) Histoplasmosis
Hope that helps
A system increases in internal energy by 80 J and 50 J of work are done on it at the same time. What is the heat change of the system
Answer:
The heat change of the system is 30 J.
Explanation:
Given;
increase in internal energy of a system, ΔU = 80 J
work done on the system, W = 50 J
The heat change of the system can be calculated from first law of Thermodynamics;
ΔU = Q - W
where;
Q is the heat absorbed by the system
W is the work done by the system (negative when work is done by the system and positive when work is done on the system)
Since work was done on the system the increase internal energy is given as;
ΔU = Q + W
ΔU - W = Q
80 J - 50 J = Q
30 J = Q
Therefore, the heat change of the system is 30 J.
Planet Zero has a mass of 4.0 x 1023 kg and a radius of 2.0 x 106 m. A 10-kg space probe is launched vertically from the surface of Zero with an initial kinetic energy of 8.0 x 107 J. What maximum distance from the center of Zero is achieved by the probe
Answer:
r2 = 1.25 × 10^(6) m
Explanation:
We are given;
Initial kinetic energy; K_1= 8.0 x 10^(7) J
Mass of planet zero; M = 4.0 x 10^(23) kg
Mass of space probe; m = 10 kg
Radius of planet zero; r1 = 2 × 10^(6) m
From conservation of energy, we can say that;
Initial potential energy + Initial kinetic energy = Final potential energy + Final kinetic energy
This is;
U1 + K1 = U2 + K2
Using formula for potential energy: U = GMm/r, we can write it as;
GMm/r1 + K1 = GMm/r2 + K2
Where Maximum distance = r2
At maximum distance from the center of Zero, K2 = 0.
Thus;
GMm/r1 + K1 = GMm/r2
Making r2 the subject, we have;
r2 = GMm/((GMm/r1)+ K1)
Where G is gravitational constant = 6.67 × 10^(-11) N/m²/kg2
Thus;
r2 = (6.67 × 10^(-11) × 4.0 x 10^(23) × 10)/((6.67 × 10^(-11) × 4.0 x 10^(23) × 10)/(2 × 10^(6)) + (8.0 × 10^(7)))
r2 = 1.25 × 10^(6) m
The electrical resistance of a circuit is influenced by the _____, _____, and _____ of the wires.
Answer:
Length, gauge/size and composition
Explanation:
The longer the wire is the more resistance
The thinner the wire is more resistance
The difference in material effects the resistance ie. copper versus aluminium.
My dog Ubu can run at 21 mi/h. How far can he travel in 40 minutes?
Answer:
14
Explanation:
21miles/3=7
7*2=14
A 100g mouse and an elephant want to find balance by sitting on a really long see-saw that is balanced at its center of mass. Of the 5000 kg elephant is sitting 0.75m away from the axis of rotation, how far away from the axis of rotation must the mouse sit
Answer:
3.75 km away
Explanation:
From the law of moments, clockwise moments = anticlockwise moment
So WL = wl where W = weight of elephant = Mg and M = mass of elephant = 5000 kg, L = distance of elephant from axis of rotation = 0.75 m, and w = weight of mouse = mg where m= mass of mouse = 100 g = 0.1 kg and l = distance of mouse from axis of rotation = unknown and g = acceleration due to gravity.
So, MgL = mgl
ML = ml
l = ML/m
= 5000 kg × 0.75 m/0.1 kg
= 3750 kgm/0.1 kg
= 37500 m
= 3.75 km away
What is the Potential Energy of a spring stretched 5.0 cm that has a
spring constant of 79 N/m?
Answer:
The Potential Energy of the stretched spring is = 1.975 J
Explanation:
Recall that the potential energy of a spring of constant k stretched x\a distance x is given by the formula:
U = 1/2 k x^2
Therefore in our case, converting the stretch from cm of meters (0.05 m), this is
U = 1/2 * 79 * 0.05 J = 1.975 J
Expert Answer please 100 points \\ Find the largest value P can have and the boxes move together with equal accelerations?
If she returned home by the same path 7 h 30 min after she left, what were her average speed and velocity in km/h for the entire trip
Answer:
speed v = 0.148 m / s
velocity v = 0
Explanation:
In this exercise we must be careful that the speed is a scalar and the speed is a vector, let's start by looking for the speed
v = Δx /Δt
the distance traveled is x = 2d and the time taken is
t = 7h 30 min
let's reduce to seconds
t = 7 h 3600s / 1h + 30 min 60s / 1min = 27000 s
so the speed is
v = 2d / 27000
to finish the calculation suppose a distance traveled d = 2000 m
v = 2 2000/27000
v = 0.148 m / s
this is the raides which is the speed module
Velocity is a vector,
v = Dx / Dt
in this case the displacement is
Dx = d -d
Dx = 0
the total displacement is zero since it returns to the starting point, consequently the velocity is zero
v = 0
bold is a vector
Given an area of 8 ft^2. Express this area in the following terms. (a)m^2 5.9458 Incorrect: Your answer is incorrect. m^2 (b) in^2 WebAssign will check your answer for the correct number of significant figures. 96 Incorrect: Your answer is incorrect. in^2 (express to 4 significant figures)
Answer:
0.7432m²
1152in²
Explanation:
a) Usng the conversion
1ft² = 0.0929m²
8ft² = y
y = 8 × 0.0929
y = 0.7432m²
Hence 8ft² in m² is 0.7432m²
For ft² to in²
1ft² = 144in²
8ft² = x
X =8×144
x = 1152in²
Hence 8ft² expressed in in² is 1152in²
Beams of light undergo construction interference when two different beams intersect to form one brighter beam of light . Which model of the nature of light dose this behavior?
Answer:the wave model
Explanation: