a)Child's speed halfway down the slide is 9.89m/s.
b)Child's speed three fourth of the way down is 12.12 m/s.
Potential energy that a massive object has in relation to another massive object due to gravity is called gravitational potential energy. Potential energy associated with the gravitational field is converted to kinetic energy when the objects falls towards each other.
As we know that, ΔPE=KE
mgΔh=mv²/2
Now, v=sqrt(2gΔh)
Halfway down the slide, Δh=5 m
gravity = 9.8 m/s²
v=sqrt(2gΔh)
v= √2* 9.8 * 5
= √98
= 9.89 m/s
For the three fourth of the way down, Δh=7.5 m.
v= √2* 9.8 * 7.5
= 12.12 m/s
To know more about gravitational potential energy, refer
https://brainly.com/question/3120930
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