Predict/Calculate You want to nail a 1.6-kg board onto the wall of a barn. To position the board before nailing, you push it against the wall with a horizontal force F → to keep it from sliding to the ground ( Figure 6-50 ) (a) If the coefficient of static friction between the board and the wall is 0.79, what is the least force you can apply and still hold the board in place? (b) What happens to the force of static friction if you push against the wall with a force greater than that found in part (a)? Figure 6-50 Problem 33
Predict/Calculate You want to nail a 1.6-kg board onto the wall of a barn. To position the board before nailing, you push it against the wall with a horizontal force F → to keep it from sliding to the ground ( Figure 6-50 ) (a) If the coefficient of static friction between the board and the wall is 0.79, what is the least force you can apply and still hold the board in place? (b) What happens to the force of static friction if you push against the wall with a force greater than that found in part (a)? Figure 6-50 Problem 33
Predict/Calculate You want to nail a 1.6-kg board onto the wall of a barn. To position the board before nailing, you push it against the wall with a horizontal force
F
→
to keep it from sliding to the ground (Figure 6-50) (a) If the coefficient of static friction between the board and the wall is 0.79, what is the least force you can apply and still hold the board in place? (b) What happens to the force of static friction if you push against the wall with a force greater than that found in part (a)?
Figure 6-50
Problem 33
Definition Definition Force that opposes motion when the surface of one item rubs against the surface of another. The unit of force of friction is same as the unit of force.
70
0• One end of a uniform
meter stick is placed against a
vertical wall (Fig. P70). The
other end is held by a light-
weight cord that makes an
angle 0 with the stick. The
Figure P70
coefficient of static friction
between the end of the meter
- x -
stick and the wall is 0.40.
(a) What is the maximum value
the angle 0 can have if the stick
is to remain in equilibrium? (b) Let the angle 0 be 15°. A block of
the same weight as the meter stick is suspended from the stick, as
shown, at a distance x from the wall. What is the minimum value of
x for which the stick will remain in equilibrium? (c) When
15°, how large must the coefficient of static friction be so that
the block can be attached 10 cm from the left end of the stick with-
out causing it to slip?
At what height in (A) must the wooden board be inclined such that the maximum static friction is obtained when the angle of repose is 32.4°?
A hand truck is used to move two
kegs, each of a mass 39 kg.
Assume g=9.8 m.s² and neglect the
weight of the hand truck.
a=30 deg.
80 mm
350 mm
300 mm
G₁
500 mm
•G2
B
a
1- Determine in N the vertical force P
that should be applied to the handle
to maintain equilibrium when a=30
deg.
Human Biology: Concepts and Current Issues (8th Edition)
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.