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#1
Figure 11 shows a child on a playground swing. The playground has a rubber safety surface.

A child of mass 32 kg jumped from the swing.
When the child reached the ground she took 180 milliseconds to slow down and stop.
During this time an average force of 800 N was exerted on her by the ground.
Calculate the velocity of the child when she first touched the ground.
0
2 months ago
#2
try the impulse formula. F × change in time = mass x velocity. rearrange for velocity = (Force × time)/mass
rember to convert from ms to s. hope this helps.
0
#3
hi, so i turned 180 ms into s (1.8) and i did 32*0.18/800 but the answer is 0.007 which doesnt seen right
0
1 month ago
#4
180 ms = 0.18 s
as 1s=1000ms
0
1 month ago
#5
How do you answer this question? I'm slightly confused
0
1 month ago
#6
(Original post by Esme9812)
How do you answer this question? I'm slightly confused
0
1 month ago
#7
You use the equation
Force x time = mass x velocity

Rearrange it
Velocity = ( force x time ) / mass

180 milliseconds is 0.18s

800 x 0.18 / 32 = 4.5 m/s
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