Question

If an arrow with the mass of 30 grams, sits in a bow with the potential energy of 70 J, what would the velocity of the arrow be after it left the bow. Assume no energy loss.

2.2 m/s
68 m/s
4.7 m/s
4700 m/s

Answer 1

Answer:

68m/s

Explanation:

Given parameters:

Mass = 30g  = 0.03kg

Potential energy  = 70J

Unknown:

Velocity  = ?

Solution;

Since there is no loss in energy, the potential energy and kinetic energy will be the same when shot;

              P.E = K.E

            K.E  =  P.E  = $\frac{1}{2}$ m v²

                        70 = $\frac{1}{2}$  x 0.03 x v²  

                         70 = 0.015v²

                           v = 68m/s