## Pushing a Boulder

In the figure below, a 500 kg boulder is pushed 40 m along a slope. What is the potential energy at the top?

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__**Hint**

**Hint**

Vertical distances are only relevant in potential energy problems. We can ignore the slope and angle.

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__**Hint 2**

**Hint 2**

Potential Energy in a Gravity Field:

$$$U=mgh$$$

where
$$m$$
is the mass,
$$g$$
is the acceleration due to gravity, and
$$h$$
is the height.

Vertical distances are only relevant in potential energy problems. We can ignore the slope and angle. For Potential Energy in a Gravity Field:

$$$U=mgh$$$

where
$$m$$
is the mass,
$$g$$
is the acceleration due to gravity, and
$$h$$
is the height. Thus,

$$$U=(500kg)(9.8m/s^2)(10m)=49,000\frac{kg\cdot m^2}{s^2}=49\:kJ$$$

49 kJ