A block of mass 3.40 kg is pushed up against a wall by a force P that makes an a
ID: 1778846 • Letter: A
Question
A block of mass 3.40 kg is pushed up against a wall by a force P that makes an angle of 50.0° angle with the horizontal as shown below. The coefficient of static friction between the block and the wall is 0.300. (a) Determine the possible values for the magnitude of P that allow the block to remain stationary. (If there is no maximum, enter NONE in that answer blank.) (b) What happens if IPI has a larger value than Pmaxl? The block slides up the wall. The block does not slide along the wall. The block slides down the wall. What happens if PI has a smaller value than Pminl? The block slides up the wall. The block does not slide along the wall. The block slides down the wall. Enter a number. (a and b) assuming the force makes an angle of 12 ge with the horizontal. Determine the possible values for the magnitude of P that allow the block to remain stationary. If there is no maximum, enter NONE in that answer blank.) What happens if PI has a larger value thanPax? The block slides up the wall. The block does not slide along the wall The block slides down the wall What happens if PI has a smaller value than Pminl? The block slides up the wall. The block does not slide along the wall. The block slides down the wall.Explanation / Answer
Weight = 3.40*9.81 = 33.354 N down
Vertical component of applied force is = P*sin50.0 degree up
then maximum frictional force will be = 0.300*Pcos50.0 degree
At a minimum value of P, friction will be up.
33.354 = P*sin50 + 0.300*P*cos50
33.354 = P*(sin50 + 0.300*cos50)
P = 33.354/(sin50 + 0.300*cos50)
P = 34.784 N
At a maximum value of P, friction will be down.
33.354 = P*sin50 - 0.300*P*cos50
33.354 = P*(sin50 - 0.300*cos50)
P = 33.354/(sin50 - 0.300*cos50)
P = 58.188 N
At a minimum value of P, friction will be up.
33.354 = P*sin12.8 + 0.300*P*cos12.8
33.354 = P*(sin12.8 + 0.300cos12.8)
P = 33.354/(sin12.8 + 0.300cos12.8)
P = 147.24 N
At a maximum value of P, friction will be down.
0.300*cos12.8 > sin12.8
Friction is greater than vertical component of P.
There is no maximum value of P.
The block will not slide up when the angle is 12.8 degree