If a marble is released from a height of 1955 cm, how long would it take to hit the ground?

1.997s = 2.0s

Explanation:

From equation of motion,

S = ut + 1/2 gt²

u = 0 m/s

t = ?

g = 9.8 m/s²

S = 1955cm = 19.55m

19.55 = 0 + 1/2 * 9.8 * t²

19.55 * 2 = 9.8t²

t² = 19.55 * 2 / 9.8

t² = 3.987

t = (3.987)^½ (take the square root of both sides)

t = 1.997s = 2.0s

electrical potential energy =0.072 j

explanation:

electrical potential energy is given by

u= q δv

q= charge=6 c

δv= potential difference and is given by

δv= e d

e= electric field

d= distance=5 mm=0.005 m

δv=2.4 (0.005)=0.012 v

now electric potential energy= u= q δv

u=6 (0.012)

u=0.072 j