Download Equal forces ~F act on isolated bodies A and B. The mass of

Phys101
Q1:
Term:131
Online HW-Ch05-Lec01
Equal forces ~F act on isolated bodies A and B. The mass of B is three times that of A.
The magnitude of the acceleration of A is:
A.
B.
C.
D.
E.
three times that of B
1/3 that of B
the same as B
nine times that of B
1/9 that of B
Ans:
A
Q2:
Ans:
While two forces acts on it, a particle is to move at the constant velocity v =
(3m/s )i-(4m/s)j. One of the forces is F 1 = (3N)i + (-4N)j. What is the
magnitude (in N) of the other force?
Since the particle moves with constant speed the net force is zero.
F 1 + F 2 =0
F 2 = -F 1
|F2 | = �32 + 42 = 5.0 N
Q3:
A 5.0 kg block is lowered with a downward acceleration of 2.8m/s2 by means of a
rope. The force of the block on the rope is?
Ans:
T − mg = −ma
T = mg − ma = 5(9.8 − 2.8) = 35N
KFUPM-Physics Department
T
ma
mg
1