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A disc at rest without slipping, rolls down a hill of height (3×9.8)m.What is its speed when it reaches at the bottom?

User MinuteMed
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1 Answer

6 votes

Answer:

The speed as it reaches the bottom is 24m/s

Step-by-step explanation:

Given parameters:

Height of hill = (3 x 9.8)m = 29.4m

Unknown:

Final speed as it reaches the bottom = ?

Solution:

To solve this problem, we apply;

v² = u² + 2gh

v is the final velocity

u is the initial velocity

g is the acceleration due to gravity = 9.8m/s²

h is the height

note, the initial speed of the body is 0;

Input the parameters and solve;

v² = 0² + 2 x 9.8 x 29.4

v² = 576.24

v = √576.24 = 24m/s

The speed as it reaches the bottom is 24m/s

User Antialiasis
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