# An object has a mass of #5 kg#. The object's kinetic energy uniformly changes from #15 KJ# to # 42KJ# over #t in [0,8s]#. What is the average speed of the object?

The average speed is

The kinetic energy is

Therefore,

and,

The equation of the line is

So,

So,

By signing up, you agree to our Terms of Service and Privacy Policy

[ \text{Average Speed} = \frac{\text{Change in Distance}}{\text{Change in Time}} ] [ \text{Average Speed} = \frac{\sqrt{2 \times \text{Change in Kinetic Energy}}}{\text{Mass} \times \text{Change in Time}} ] [ \text{Average Speed} = \frac{\sqrt{2 \times (42 , \text{KJ} - 15 , \text{KJ})}}{5 , \text{kg} \times 8 , \text{s}} ] [ \text{Average Speed} \approx \frac{\sqrt{2 \times 27 , \text{KJ}}}{40 , \text{kg} , \text{s}^{-1}} ] [ \text{Average Speed} \approx \frac{\sqrt{54} , \text{KJ}}{40 , \text{kg} , \text{s}^{-1}} ] [ \text{Average Speed} \approx \frac{7.35 , \text{KJ}}{40 , \text{kg} , \text{s}^{-1}} ] [ \text{Average Speed} \approx 0.184 , \text{KJ} , \text{kg}^{-1} , \text{s}^{-1} ]

By signing up, you agree to our Terms of Service and Privacy Policy

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.

- What is the average speed of an object that is still at #t=0# and accelerates at a rate of #a(t) = 2t^2-2t+2# from #t in [0,2]#?
- A projectile is shot from the ground at a velocity of #1 m/s# at an angle of #pi/4#. How long will it take for the projectile to land?
- An object is dropped off a building measuring 65m tall. How long does it take for the object to fall?
- If an object with uniform acceleration (or deceleration) has a speed of #2 m/s# at #t=0# and moves a total of 20 m by #t=4#, what was the object's rate of acceleration?
- An object is at rest at #(3 ,8 ,8 )# and constantly accelerates at a rate of #7/5 m/s^2# as it moves to point B. If point B is at #(2 ,9 ,1 )#, how long will it take for the object to reach point B? Assume that all coordinates are in meters.

- 98% accuracy study help
- Covers math, physics, chemistry, biology, and more
- Step-by-step, in-depth guides
- Readily available 24/7