10th grade energy

Question 1

A ball is dropped from a height of 2 m. Ignoring air resistance, how fast is it moving just before it hits the ground, in m/s? (g = 9.8 N/kg; give 1 decimal place)

Answer m/s

Question 2

A 2 kg object falls 2 m. 40 % of its gravitational potential energy is transferred to the surroundings by air resistance. How much kinetic energy does it have at the bottom, in J? (g = 9.8 N/kg; give 1 decimal place)

Answer J

Question 3

A skateboarder leaves the bottom of a ramp at 7 m/s. Ignoring friction, what is the greatest height they can reach, in m? (g = 9.8 N/kg; give 2 decimal places)

Answer m

Question 4

A stretched bow is released and the arrow flies off. Which energy transfer happens?

• A. thermal → elastic
• B. elastic potential store of the bow → kinetic store of the arrow
• C. kinetic → elastic
• D. chemical → nuclear

Question 5

A spring with spring constant 40 N/m is stretched by 0.5 m. How much energy is stored in it, in J?

Answer J

Question 6

A catapult band has a spring constant of 200 N/m and is pulled back 4 cm. How much elastic potential energy is stored, in J? Give 3 decimal places.

Answer J

Question 7

A ball is dropped from a height of 1 m. Ignoring air resistance, how fast is it moving just before it hits the ground, in m/s? (g = 9.8 N/kg; give 1 decimal place)

Answer m/s

Question 8

A 60 kg object falls 15 m. 10 % of its gravitational potential energy is transferred to the surroundings by air resistance. How much kinetic energy does it have at the bottom, in J? (g = 9.8 N/kg; give 1 decimal place)

Answer J

Question 9

A skateboarder leaves the bottom of a ramp at 7 m/s. Ignoring friction, what is the greatest height they can reach, in m? (g = 9.8 N/kg; give 2 decimal places)

Answer m

Question 10

Work is done stretching a spring that obeys Hooke's law. How can this work be found from a force–extension graph?

• A. the area under the line
• B. the length of the line
• C. the gradient of the line
• D. the highest force only

Question 11

A spring with spring constant 400 N/m is stretched by 0.2 m. How much energy is stored in it, in J?

Answer J

Question 12

A catapult band has a spring constant of 250 N/m and is pulled back 20 cm. How much elastic potential energy is stored, in J? Give 3 decimal places.

Answer J

Question 13

A ball is dropped from a height of 2 m. Ignoring air resistance, how fast is it moving just before it hits the ground, in m/s? (g = 9.8 N/kg; give 1 decimal place)

Answer m/s

Question 14

A 5 kg object falls 15 m. 10 % of its gravitational potential energy is transferred to the surroundings by air resistance. How much kinetic energy does it have at the bottom, in J? (g = 9.8 N/kg; give 1 decimal place)

Answer J

Question 15

A skateboarder leaves the bottom of a ramp at 20 m/s. Ignoring friction, what is the greatest height they can reach, in m? (g = 9.8 N/kg; give 2 decimal places)

Answer m

Question 16

Work is done stretching a spring that obeys Hooke's law. How can this work be found from a force–extension graph?

• A. the highest force only
• B. the length of the line
• C. the gradient of the line
• D. the area under the line