Question

mission we4: mechanical energy
suppose an object speeds up while moving horizontally. in this situation, the objects kinetic energy would __, its potential energy would , and its total mechanical energy would __. enter the three letters in their respective order.
a. increase
b. decrease
c. remain the same
d. ... nonsense! it is impossible to tell without additional info.

Explanation:

• Kinetic energy formula is \(KE=\frac{1}{2}mv^{2}\). Since the object speeds up (\(v\) increases) and mass \(m\) is constant, kinetic energy increases.
• The object is moving horizontally. Assuming no change in height (for gravitational potential energy, \(PE = mgh\), \(h\) is constant) and no spring - like compression/extension (for elastic potential energy), potential energy remains the same.
• Total mechanical energy \(E=KE + PE\). As \(KE\) increases and \(PE\) remains the same, total mechanical energy increases.

Answer:

a, c, a