I need help with the following conceptual questions and the problems numbered 2, 4, 32, 36, 38.

1. A friend tells you that since his car is at rest there are no forces acting on it. How would you reply?

6. Riding in an elevator moving with a constant speed, you begin a game of darts. Do you have to aim your darts higher,
lower or the same as when you play darts on solid ground?

20. A surfer hangs ten and acc down the sloping face of a wave. If the surfer acceleration is 3.25 m/s2 and the friction
can be ignored, what is the angle at which the face of the wave is inclined above the horizontal?

25. A 65kg skier speeds down a trail, the surface is smooth and inclined at an 22 degrees with the horizontal.

(a) Find the direction and magnitude of the net force acting on the skier.
(b) Does the net force exerted on the skier increase, decrease, or stay the same as the slope becomes steeper?

37. A 23 kg suitcase is being pulled with constant speed by a handle that is at an angle 25 degrees above the horizontal. If
the normal force exerted on the force is 180 N, what is the force F applied to the handle?

39. A 9.3 kg child sits in a 3.7 kg high chair.

(a) Draw a free body diagram for the child and find the normal force exerted by the chair on the chills.
(b) Draw a free body diagram for the chair and find the normal force exerted by the floor on the chair.

42. Find the normal force exerted on a 2.7 kg book resting on a surface inclined at 32 degrees above the horizontal.

(a) If the angle of the incline is reduced do you expect the normal force to Increase, decrease, or stay the same?

50. Biomechanical research has shown that when a 67 kg person is running, the force exerted on each foot as it strikes the
ground can be as great as 2300 N.

(a) What is the ratio of the force exerted on the foot by the ground to the person's body weight?
(b) If the only forces acting on the person are (i) the force exerted by the ground and (ii) the person's weight, what is
the magnitude and direction of the person's acceleration? C. If the acceleration found in part (b) acts 10.0 ms, what is
the resulting change in the vertical component of the person's velocity?

Need help with the equation/solution to this problem.
An individual weighing 600 N stands still with her hips flexed. Her hip extensor muscles are contracting with a force of 3000 N, and her ankle plantarflexor muscles with a force of 3200 N. What is the magnitude of the ground reaction force acting on her?

While constructing a space platform a 116kg robot finds itself standing on a 24m long 205 kg steel beam that is motionless with respect to the platform. Using its magnetic feet it walks along the beam traveling south at 2.45m/s. What is the velocity of the beam with respect to the platform as the robot walks?

The following equations describe the motion of a system of two objects:
+n - (5.00 kg)(9.8 m/s2)cos 15.0° = 0
fk = 0.360n
+T + (5.00 kg)(9.8 m/s2)sin 15.0° - fk = (5.00 kg)a
-T + (3.10 kg)(9.8 m/s2) = (3.10 kg)a
(a) Solve the equations for a and T.
a (in m/s2)=
T (in N)=
In what situation might these equations be u

The weight of the block in the drawing is 80.2 N. The coefficient of static friction between the block and the vertical wall is 0.490.
(a) What minimum force F is required to prevent the block from sliding down the wall?
(b) What minimum force is required to start the block moving up the wall?

A block of mass m1 = 4.70 kg sits on top of a second block of mass m2 = 16.3 kg, which in turn is on a horizontal table. The coefficients of friction between the two blocks are µs = 0.300 and µk = 0.100. The coefficients of friction between the lower block and the rough table are µs = 0.600 and µk = 0.500. You apply a consta

Determine the specific gravity of spherical particles, D=(1/200 in), which drop through air at 33degrees F at a speed U of 0.3 ft/s. The drag force on a small sphere in laminar motion is given by 3(pi)(mu)DU.
This problem is in Fluid Mechanics by Victor Streeter.

An athlete whose mass is m is performing weight-lifting exercises. Starting from the rest position, he lifts, with constant acceleration, a barbell that weighs w. He lifts the barbell a distance of x in a time of t.
Use Newton'slaws to find the total force that his feet exert on the ground as he lifts the barbell.
Take free

A 4.0 kg toboggan rests on a frictionless icy surface, and a 2.0 kg block rests
on top of the toboggan. The coefficient of static friction µs between the block
and the surface of the toboggan is 0.58, whereas the kinetic friction
16.T op
coefficient is 0.48. The block is pulled by a horizontal force of 30 N as shown.
a. Ca

Please provide a detailed step by step solution and explanation to this problem.
Suzie (50kg) is roller-blading down the sidewalk going 20 miles per hour. She notices a group of workers down the walkway who have unexpectedly blocked her path, and she makes a quick stop in 0.5 seconds.
a) What is Suzie's average acceler