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

68m/s

Step-by-step 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 =
`(1)/(2)` m v²

70 =
`(1)/(2)` x 0.03 x v²

70 = 0.015v²

v = 68m/s