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Tiger, a cat whose mass is 5.45 kg, is napping on top of the refrigerator when he rolls over a falls off. Tiger has a KE of 85.5 J just before he lands with his feet on the floor. How tall is the refrigerator?

User Dre
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1 Answer

15 votes
15 votes

Answer:

Step-by-step explanation:

Tiger is going at a final speed that can be found by

KE = 1/2 m v^2

KE = 1/2 * 5.45 kg * v^2

85.5 = 1/2*5.45 * v^2 Multiply both sides by 2

85.5 *2 = 5.45 v^2 Combine

171 = 5.45 v^2 Divide by 5.45

171 / 5.45 =5.45 v^2 / 5.45

31.38 = v^2

v^2 = 31.38 Take the square root of both sides.

√v^2 = √31.38

v = 5.60 m/s

V actually is vf. It is the final velocity reached by the cat just before he hits the ground.

Now we have to solve for d. Tiger was asleep. Presumably his starting speed was 0

vo = 0

vf = 5.60

a = 9.81

d = ?

Formula

vf^2 = vi^2 + 2*a * d

Solution

Substitute for the variables

5.60^2 = 0 + 2 * 9.81 * d

31.38 = 19.62 d Divide both sides by 19.62

31.38/19.62 = d * 19.62 / 19.62

d = 1.60 meters.

User Juozas
by
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