Answer:
9.4 m/s
Explanation:
The work-energy theorem states that the work done on an object is equal to the change in kinetic energy of the object.
So we can write:
where in this problem:
W = -36.733 J is the work performed on the car (negative because its direction is opposite to the motion of the car)
is the initial kinetic energy of the car
is the final kinetic energy
Solving for Kf,
The kinetic energy of the car can be also written as
where:
m = 661 kg is the mass of the car
v is its final speed
Solving, we find
Answer:
Explanation:
m = Mass of person = 70 kg
c = Specific heat of human body = 
= Change in temperature
Time taken is 1 hour
Heat is given by
The rise in temperature is 
Answer:
x = 41.28 m
Explanation:
This is a projectile launching exercise, let's find the time it takes to get to the base of the cliff.
Let's start by using trigonometry to find the initial velocity
cos 25 = v₀ₓ / v₀
sin 25 = Iv_{oy} / v₀
v₀ₓ = v₀ cos 25
v_{oy} = v₀ sin 25
v₀ₓ = 22 cos 25 = 19.94 m / s
v_{oy} = 22 sin 25 = 0.0192 m / s
let's use movement on the vertical axis
y = y₀ + v_{oy} t - ½ g t²
when reaching the base of the cliff y = 0 and the initial height is y₀ = 21 m
0 = 21 + 0.0192 t - ½ 9.81 t²
4.905 t² - 0.0192 t - 21 = 0
t² - 0.003914 t - 4.2813 =0
we solve the quadratic equation
t = 
t = 
t₁ = 2.07 s
t₂ = -2.067 s
since time must be a positive scalar quantity, the correct result is
t = 2.07 s
now we can look up the distance traveled
x = v₀ₓ t
x = 19.94 2.07
x = 41.28 m
10 mph/s because there is 60 seconds in a minute then divide by 6 which is 10.
Here We can use principle of angular momentum conservation
Here as we know boy + projected mass system has no external torque
Since there is no torque so we can say the angular momentum is conserved
now we know that
m = 2 kg
v = 2.5 m/s
L = 0.35 m
I = 4.5 kg-m^2
now plug in all values in above equation
![1.75 = [4.5 + 0.245]\omega](https://tex.z-dn.net/?f=1.75%20%3D%20%5B4.5%20%2B%200.245%5D%5Comega)
so the final angular speed will be 0.37 rad/s
