Question

hy
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ans it quickly
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no wrong answers
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Answer 1

122.5 = Ut +0.5 at^2
= 0.5×9.8×t^2
t^2= 122.5/4.9= 25
t= 5 s.
now in three seconds
s= ut +0.5 × 10× 3×3 = 5×9 =45 metres.
and
V=u+at
=0+10×3 = 30s

Answer 2

Given Distance s = 122.5m, Initial velocity u = 0, a = 9.8m/s^2.

(i) we know that s = ut + (1/2) * at^2

= > 122.5 = (1/2) * (9.8) * t^2

= > 122.5 = 4.9 * t^2

= > 122.5/4.9 = t^2

= > 25 = t^2

= > t = 5.

It will take 5 seconds to fall on the ground.

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(ii)

Given t = 3 seconds, a = 9.8 m/s^2, u = 0.

We know that s = ut + (1/2) * at^2

= > (1/2) * 9.8 * (3)^2

= > (4.9) * 9

= > 44.1.

It will cover 44.1 m in the 1st 3 seconds.

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(iii)

Given t = 3 seconds, a = 9.8 m/s^2, u = 0.

We know that v = u + at

= > 0 + (9.8) * 3

= > (9.8) * 3

= > 29.4 m/s.

It's speed is 29.4 m/s.

Hope it helps!