A ball bearing is projected vertically upwards from the ground with a velocity of 15ms^-1. Calculate the time taken by the ball to return to the ground [g = 10ms^-1]

Tobscollins

10 years ago

Time taken to return to the group is 1.5,bt d total time taken is 3s,bt d question is only concern abt d time it returned to the ground, not the total time

feranmiadam

3 years ago

t= 2(v-u)/g
t=2(0-15)/-10
t=2×15/10
t=3.0s

NnamaniChibuikemGabriel370

2 years ago

U=15m/s, t=? g=10m/s^2
T= 2U/g
T= 2×15/10
T= 30/10
T= 3 seconds.

Folafoluwa2007

1 year ago

You can also try
S=ut+1/2at^2
where
a=-10(gravity acting downward )
S=0(because the ball lands back at the starting point)
U=15m/s
V=0m/s

S=ut+1/2at^2
0=15t+1/2(-10)t^2
0=15t-5t^2 [i.e 1/5×(-10)=-5]
5t^2=15t
Divide both sides by 5t
t=15t/3t
t=3 seconds