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3 years ago

49. A block is pushed across a horizontal surface with a

Physics

1 answer:

nata0808 [166]3 years ago

8 0

Answer:

(a) 37.5 kg

(b) 4

Explanation:

Force, F = 150 N

kinetic friction coefficient = 0.15

(a) acceleration, a = 2.53 m/s^2

According to the newton's second law

Net force = mass x acceleration

F - friction force = m a

150 - 0.15 x m g = m a

150 = m (2.53 + 0.15 x 9.8)

m = 37.5 kg

(b) As the block moves with the constant speed so the applied force becomes the friction force.

$F = \mu m g \\\\150 = \mu\times 37.5\\\\\mu = 4$

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