Physics Force & Laws Of Motion Level: High School
Block A , with a mass of 10 kg , rest on a 35 degree incline . The coefficient of static friction is 0.40 . An attached string is parallel to the incline and passes over a massless , frictionless pulley at the top . Find the smallest mass mB , attached to the dangling end , for which A remains at rest is
Physics Force & Laws Of Motion Level: High School
The system shown in the figure at “click here” remains at rest . Find the force of friction on the upper block .
Physics Force & Laws Of Motion Level: High School
A block is first placed on its long side and then on its short side on the same inclined plane . The block slides down the plane on its short side but remain at rest on its long side . A possible explanation is .A. the short side is smoother.
B. the frictional force is less because the contact area is less.
C. the center of gravity is higher in the second case.
D. the normal force is less in the second case.
E. the force of gravity is more nearly down the plane in the second case.
Physics Force & Laws Of Motion Level: High School
A 400-N block is dragged along a rough (uk = 0.4 ) horizontal surface by an applied force F as shown in the figure at “click here” . The block moves at constant velocity . Find the magnitude of F :
Physics Force & Laws Of Motion Level: High School
A boy pulls a wooden box along a rough horizontal floor at constant speed by means of a force P as shown in the figure at “lick here”. In the diagram f is the magnitude of the force of friction. N is the magnitude of the normal force , and Fg is the magnitude of the force of gravity . Which of the following must be true ?A. p = f and N = Fg
B. p = f and N > Fg
C. p > f and N < Fg
D. p > f and N = Fg
E. none of the above.
Physics Force & Laws Of Motion Level: High School
A horizontal shove of at least 200-N is required to start moving a 800-N crate initially at rest on a horizontal floor . Find the coefficient of static friction .
Physics Force & Laws Of Motion Level: High School
A brick slides on a horizontal surface. Which of the following will increase the frictional force on it ?A. Putting a second brick on top.
B. Decreasing the surface area of contact.
C. Increasing the surface area of contact.
D. Decreasing the mass of the brick
E. None of the above.
Physics Force & Laws Of Motion Level: High School
Two blocks with masses m and M are pushed along a horizontal frictionless surface by a horizontal applied force F as shown in the figure at “click here” . The magnitude of the force that either of these blocks exerts on the other isa) mFl(m+M)
b) mFlM
c) mFl(M-m)
d) MFl(M+m)
e) MFlm
Physics Force & Laws Of Motion Level: High School
Three blocks (A,B,C) each having mass M , are connected by string as shown in the figure at “click here”. Block C is pulled to the right by a force F that causes the entire system to accelerate . Neglecting friction. Find the net force acting on block B .
Physics Force & Laws Of Motion Level: High School
Two blocks weighing 250 N and 350 N respectively , are connected by a string that passes over a massless pulley as shown in the figure at “click here” Calculate the tension in the string .
Physics Force & Laws Of Motion Level: High School
The “reaction” force does not cancel the “action” force because :a) the action force is greater than the reaction force .
b) they act on different bodies .
c) they are in the same direction .
d) the reaction force exists only after the action force is removed .
e) the reaction force is greater than the action force .
Physics Force & Laws Of Motion Level: High School
A 1.5 N ball is thrown at an angle of 30 degree above the horizontal with an initial speed of 12 m/s. At its highest point , the net force on the ball isa) 9.8 N , 30 degree below horizontal
b) zero
c) 9.8 N , up
d) 9.8N , down
e) 1.5N , down
Physics Force & Laws Of Motion Level: High School
A 25 kg chair is pushed across a frictionless horizontal floor with a force of 20N , directed 20 degree below the horizontal . The acceleration of the chair is :a) 0.27 m/s^2
b) 0.75 m/s^2
c) 0.80 m/s^2
d) 170 m/s^2
e) 470 m/s^2
Physics Force & Laws Of Motion Level: High School
The block shown moves with constant velocity on a horizontal surface . Two of the forces acting on the block are shown a frictional force exerted by the surface is the only other horizontal force acting on the block . The friction force isa) 0
b) 2N. leftward
c) 2N. rightward
d) slightly more than 2N, leftward
e) slightly less than 2N, leftward.
Physics Force & Laws Of Motion Level: High School
A heavy wooden block is dragged by a force F along a rough steel plate , as shown in the figure at “click here”. The magnitude of the applied force F is the same for both cases . The normal force in (ii) , as compared with the normal force in (i) is :a) the same
b) greater
c) less
d) less for some angles of the incline and greater for others
e) less or greater, depending on the magnitude of the applied force F
