What is a system?

• An object or a group of objects

• A computer

• Nothing is a system

• I don't know

What is the energy transfer when an object is projected upwards?

• Kinetic to Gravitational potential

• Gravitational potential to Kinetic

• Kinetic into elastic potential

• Chemical into kinetic

Answer explanation

The object's energy is initially in the kinetic store as it moves upwards. The object's energy is slowly transferred from the kinetic store to the gravitational potential store as it slows down and climbs higher. Once the object reaches its highest point, all of its energy is in the gravitational potential store. As the object falls again, energy transfers from the gravitational potential store to the kinetic store.

What is the energy transfer when a moving object hits an obstacle? (2 possible answers)

• Kinetic store in the object to the kinetic store of the obstacle

• Kinetic store of the object to the thermal store of the obstacle

• Kinetic store of the object to the nuclear store of the obstalce

• Kinetic store of the object to the chemical store of the obstacle

Answer explanation

The object's energy is in the kinetic store at the start because it is moving. When the object collides with the obstacle, energy is converted to: The kinetic store of the obstacle (making it move), The thermal store of the object and the obstacle (the particles in the object and the obstacle vibrate more). Some energy remains in the object's kinetic store as it moves away after the collision.

What is the energy transfer when an object is accelerated by a constant force?

• Work is done by a force and transferred into the kinetic store of the object

• Work is done by a force and transferred to the object's chemical store

• Work is done by a force and transferred the object's Nuclear store

What are the energy transfers when a vehicle slows down by using it's brakes?

• Kinetic store into thermal store

• Kinetic store into gravitational potential store

• Kinetic store into nuclear store

• Kinetic store into magnetic store

Answer explanation

o begin with, the vehicle's energy is in the kinetic store. The brakes do work slowing the car down. During this process, energy is dissipated (lost) through heat and sound.

How much work is done by a force of 10N pushing a block 5m

• 50

• 2

• 0.5

• 500

What is the equation for Kinetic energy?

• KE = 0.5 x m x v x v

• KE = m x g x h

• KE = 0.5 x k x e x e

Calculate the kinetic energy of a 10kg object moving at 5m/s

Answer explanation

KE = 0.5 x m x v x v

What is the equation for elastic potential energy?

• EPE = 0.5 x k x e x e

• EPE = m x g x h

• EPE = 0.5 x m x v x v

• EPE = m x c x T

Calculate the elastic potential energy of a spring with spring constant 25N/m and an extension of 4m

Answer explanation

EPE = 0.5 x k x e x e