Forces, Work, Power and Weight

A force is anything which causes an object to
1. change its weight
2. change its velocity
3. change its size
4. change its mass
Force is measured in
1. Joules
2. Pascals
3. Newtons
4. Kilograms
Hookes Law states that when a force is applied to a spring,
1. 10 newtons equals 1 kilogram of weight
2. the extension of the spring is one 1 cm for every 1 newton force appled.
3. the extension of the spring is in direct proportion to the size of the force appled to it
4. if the force is too large the spring will not return to its original shape.
Friction is
1. a force which prevents easy movement between two objects in contact
2. the energy formed when two objects in contact move against each other
3. the force of movement that an object has when in contact with another object
4. the energy formed (usually heat) when two objects do not move easily against one another
Two spring balances are hooked together and one is pulled until the reading on it shows 8 N. What is the reading on the other balance?
1. 8 kg
2. 4N
3. 8 g
4. 8N
Which of the following are useful for reducing friction?
1. rubber
2. glue
3. oil
4. a newton balance
The weight of an object
1. varies depending on where you are
2. does not change
3. depends on its size
4. depends on its volume
A car of mass 1000 kg on earth has a weight of
1. 100 N
2. 1000 N
3. 10000N
4. 10000 kg
The force of gravity on the moon is
1. 6 times that of the force of gravity on earth
2. one-sixth that of the force on earth
3. almost none
4. half of that of the force on earth
A gardner pushing a wheelbarrow exerts a force of 200 N over a distance of 20 m. How much work is done?
1. 400 kJ
2. 4000 kJ
3. 400 J
4. 4000 J
A crane lifts a slab of concrete that weighs 80,000 N from the ground up to a platform 20 m from the ground in 20 seconds. What is the power of the crane?
1. 80 kW
2. 80 W
3. 8000 W
4. 800 kW
A boy of mass 40 kg runs up a flight of 12 steps, each 0.25 m high, in 5 s. What is his power?
1. 240 J
2. 240 W
3. 240 kJ
4. 240 kW
On earth, a bag of sugar of mass 500g has a weight of
1. 50 N
2. 0.5 kg
3. 0.5 N
4. 5 N
An astronaut has a mass of 132 kg, What is his weight on the moon?
1. 220 N
2. 22 N
3. 1320 N
4. 13.2 N

Forces, Work, Power and Weight

Quiz