Questions: A 17. An 72 kg man is lifted by a helicopter 15 m vertically by a cable. a=9 / 10. How much work is done by: a) The force from the helicopter?

Solution Steps

The force exerted by the helicopter is equal to the gravitational force acting on the man, which is his weight. The weight $W$ can be calculated using the formula:

$$W = m \cdot g$$

where $m = 72 \, \text{kg}$ is the mass of the man and $g = 9.81 \, \text{m/s}^2$ is the acceleration due to gravity.

Substitute the given values into the formula:

$$W = 72 \, \text{kg} \times 9.81 \, \text{m/s}^2 = 706.32 \, \text{N}$$

The work done by the force from the helicopter is given by the formula:

$$\text{Work} = F \cdot d \cdot \cos(\theta)$$

where $F = 706.32 \, \text{N}$ is the force, $d = 15 \, \text{m}$ is the distance, and $\theta = 0^\circ$ because the force and displacement are in the same direction.

Since $\cos(0^\circ) = 1$, the work done is:

$$\text{Work} = 706.32 \, \text{N} \times 15 \, \text{m} \times 1 = 10594.8 \, \text{J}$$

Final Answer