Physics Force & Laws Of Motion Level: High School
A 0.25 kg ball moving horizontally at 10 m/s is hit by a bat which reverses the balls direction. Its final velocity is 16 m/s . The bat acts on the ball for 0.015 s. Find the average force exerted on the ball by the bat ?
Physics Force & Laws Of Motion Level: High School
A 70 gram body is projected up a rough incline plane, inclined at an angle of 35 degrees to the horizontal, with an initial velocity of 400 cm/sec . The coefficient of friction between the body and the plane is ½ . How far up the plane will the body go ?
Physics Force & Laws Of Motion Level: High School
A 1200 lb sled is pulled along a horizontal surface at uniform speed by means of a rope that makes an angle of 30 degrees above the horizontal . If the tension, T , in the rope is 100 lbs , what is the coefficient of friction ?
Physics Force & Laws Of Motion Level: High School
A 5 lb weight suspended from a 3 ft cord is pulled to one side by a horizontal force F , so that the cord makes an angle of 30 degrees with the vertical . What is the value of the force F , and what is the value of T , the tension of the cord ?
Physics Force & Laws Of Motion Level: High School
A sled may be either pulled with a rope or pushed from behind . Assume that in either case , the propelling force acts an angle of 45 degrees above the ground .A. Draw the free body diagrams for both alternatives
B. Which would be feel the most efficient ? why ?
Physics Force & Laws Of Motion Level: High School
An old car, with out ABS , is moving down the road at a speed , V. Ahead is an accident . The driver has two choices to stop: either locks the brakes or skid to a stop , or pumps the brakes , keep the wheels rolling until coming to a stop . Which will get the car to stop more quickly ? why ? identify any assumptions you make in answering this question .Physics Force & Laws Of Motion Level: High School
A block of mass m is at rest lying on the face of an incline plane . The plane makes an angle with the horizontal .A . Draw the free body diagram showing all the forces acting on the block .
B . Write the equations for the net forces acting on the block .
Physics Force & Laws Of Motion Level: High School
Block A , with a mass of 10 kg, rest on a 30 degree incline . The coefficient of kinetic friction is 0.20 . The attached string is parallel to the incline and passes over a massless , frictionless pulley at the top . Block B with a mass of 3.0 kg , is attached to the dangling end of the string . Find the acceleration of B . (magnitude and direction) :
Physics Force & Laws Of Motion Level: High School
Why do raindrops fall with constant speed during the later stages of their descent ?A. The gravitational force is the same for all drops.
B. Air resistance just balances the force of gravity.
C. The drops all fall from the same height.
D. The force of gravity is negligible for objects as small as raindrops.
E. Gravity cannot increase the speed of the falling object to more than 22 ft/s.
Physics Force & Laws Of Motion Level: High School
A 1000 kg airplane moves in straight flight at constant speed . The force of air friction is 1800 N . The net force on the plane is :A. zero
B. 11800 N
C. 1800 N
D. 9800 N
E. none of these
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.
