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2 years ago

10

A block with mass m1 = 9.4 kg is on an incline with an angle θ = 25° with respect to the horizontal. For the first question ther

e is no friction, but for the rest of this problem the coefficients of friction are: μk = 0.22 and μs = 0.242. 1)When there is no friction, what is the magnitude of the acceleration of the block?

1 answer:

NeX [460]2 years ago

7 0

Answer:

a= 4.14 m/s²

Explanation:

We calculate the weight component parallel to the displacement of the block:

We define the x-axis in the direction of the inclined plane , 25° to the horizontal.

W= m*g : Total block weight

Wx= W*sen25°= m*g* sen25°

We apply Newton's second law :

∑F = m*a (Formula 1)

∑F : algebraic sum of the forces in Newton (N)

m : mass in kilograms (kg)

a : acceleration in meters over second square (m/s²)

Problem development

We apply the formula (1) to calculate the acceleration of the block:

∑Fx = m*a

Wx = m*a

m*g* sen25° = m*a : We divide by m on both sides of the equation

g* sen25° = a

a = g* sen25° = 9.8* sen25° = 4.14 m/s²

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