Work: Everyday and Scientific Meaning

A person pushes a wheelbarrow and it moves. According to the scientific meaning, why is this considered "work"?

• Because the person is doing a job

• Because energy is transferred to the wheelbarrow by applying force, causing it to move

• Because the wheelbarrow is heavy

• Because the person is wearing a uniform

What are the two conditions that must be met for work to be done on an object?

• The object must move and force must be applied in the direction of the movement.

• The object must be heavy and force must be applied upwards.

• The object must be stationary and force must be applied sideways.

• The object must move and force must be applied in any direction.

Work is measured in which unit?

• Joules

• Newtons

• Watts

• Meters

A 1 kg book is lifted 2 m. How much work was done?

• 10 J

• 20 J

• 2 J

• 12 J

250 J of work are needed to push a box up a ramp. The force needed to push the box up the ramp is 10.0 N. How far up the ramp was the box pushed?

• 10 m

• 25 m

• 20 m

• 15 m

A box is pushed up a ramp with a force of 10 N and 250 J of work is done. How would you calculate the distance the box was pushed? Explain your reasoning.

• Divide work by force

• Multiply force by distance

• Add force and work

• Subtract force from work

What is the formula for calculating power?

• P = W + t

• P = W/t

• P = t/W

• P = W × t

Which unit is used to measure power?

• Joules (J)

• Seconds (s)

• Watts (W)

• Meters (m)

What does the symbol 'W' represent in the formula for power?

• Work

• Watts

• Weight

• Water

If 3,150 joules of work is done in 150 seconds, what is the power required to move the refrigerator?

• 21 J/s or 21 Watts

• 315 J/s or 315 Watts

• 2.1 J/s or 2.1 Watts

• 150 J/s or 150 Watts