Question

You are helping your friend move a new refrigerator into his kitchen. You apply a horizontal force of 280 N in the positive x direction to try and move the 63 kg refrigerator. The coefficient of static friction is 0.55.

Answer 1

Complete Question

You are helping your friend move a new refrigerator into his kitchen. You apply a horizontal force of 280 N in the positive x direction to try and move the 63 kg refrigerator. The coefficient of static friction is 0.55.

(a) How much static frictional force does the floor exert on the refrigerator? Give both magnitude and direction.

magnitude N

direction

(b) What maximum force do you need to apply before the refrigerator starts to move?

Answer:

a

The magnitude is
`F_f = 339.57 \ N`

The direction is [negative x - axis ]

b

The maximum force to be applied for the refrigerator to start moving is

`F_(max) = 339.57 \ N`

Step-by-step explanation:

From the question we are told that

The horizontal force applied is
`F_a = 280 \ N` the direction is +ve x-axis

The mass of the refrigerator is
`m = 63 \ kg`

The coefficient of static friction is
`\mu_s = 0.55`

Generally the frictional force exerted on the refrigerator is mathematically represented as

`F_f = \mu * m * g`

=>
`F_f = 0.55 * 63 * 9.8`

=>
`F_f = 339.57 \ N`

From the value obtained we see that the static force exerted by the floor on the refrigerator is greater than the force (280 N ) exerted by the person and the direction is -ve x-axis

Generally the maximum force that is to be applied by the person is mathematically equal to the force exerted by the floor on the refrigerator but the direction is in the positive x-axis i.e

`F_(max) = F_f = 339.57 \ N`