Question

What does an object’s kinetic energy depend on ?

it’s mass and speed
it’s weight and speed
it’s potential energy
it’s speed and trajectory

Two city buses are traveling at 24 miles per hour. The buses are the same model and year.
One bus has 30 passengers. The other bus has 12 passengers. Which is the best
prediction? (1 point)
O The buses will have the same amount of kinetic energy.
© The buses' kinetic energies will depend on their routes.
O The bus with 12 passengers will have less kinetic energy.
O The bus with 30 passengers will have less kinetic energy.

A softball player hits a ball at 78 miles per hour. Then she hits a ball at 80 miles per hour.
Which is the best prediction? (1 point)
O The ball hit at 78 miles per hour will have more kinetic energy.
O The ball hit at 80 miles per hour will have more kinetic energy.
O
The balls' kinetic energies will depend on the distances they travel.
O
The balls will have the same amount of kinetic energy.

A hawk is chasing a sparrow. At the beginning of the chase, the hawk's kinetic energy is 5.1
Joules. At the end of the chase, the hawk doubles its speed. What is the best prediction for
its kinetic energy at the end of the chase? (1 point)
O 10.2 J
O 2.55 J
Jhn
O 20.4 J
0 51 J

A student rolls two marbles down an inclined plane. One marble has a mass of 4.8 grams.
The student calculates its kinetic energy to be 0.0035 Joules when it reaches the end of the
plane. The second marble has a mass of 2.4 grams. What is the best prediction for its
kinetic energy at the end of the plane? (1 point)
O 0.00175 J
O 0.0035 J
0.007 J
O 0.014 J

Answer 1

An object's kinetic energy depends on its mass and speed.

Two city buses are traveling at 24 miles per hour with different numbers of passengers. The bus with more passengers will have more kinetic energy, as the kinetic energy is proportional to the mass of the object.
A softball player hits a ball at 78 miles per hour and then hits a ball at 80 miles per hour. The ball hit at 80 miles per hour will have more kinetic energy as the kinetic energy is proportional to the square of the velocity.
A hawk is chasing a sparrow. At the beginning of the chase, the hawk's kinetic energy is 5.1 Joules. If the hawk doubles its speed, its kinetic energy will increase four-fold, to 20.4 Joules.
A student rolls two marbles down an inclined plane, one with a mass of 4.8 grams and the other with a mass of 2.4 grams. The kinetic energy of an object is proportional to the square of its velocity, and the kinetic energy of an object is proportional to its mass. So the second marble with a mass of 2.4 grams will have half the kinetic energy of the first marble, or 0.00175 Joules

Answer 2

It's Mass and Speed

The bus with 12 passengers will have less kinetic energy

The ball hit at 80 miles per hour will have more kinetic energy

20.4 J

0.00175 J

Step-by-step explanation:

devangyan4 is correct 100% but here is it more clear.