Advertisements
Advertisements
Question
Two bodies of masses 10 kg and 20 kg respectively kept on a smooth, horizontal surface are tied to the ends of a light string. A horizontal force F = 600 N is applied to
- A,
- B along the direction of string. What is the tension in the string in each case?
Advertisements
Solution
Horizontal force, F = 600 N
Mass of body A, m1 = 10 kg
Mass of body B, m2 = 20 kg
Total mass of the system, m = m1 + m2 = 30 kg
Using Newton’s second law of motion, the acceleration (a) produced in the system can be calculated as:
F = ma
`:.a = F/m = 600/30 = 20 "m/s"^2`
(i) When force F is applied to body A:
The equation of motion can be written as:
F-T = m1a
T = F - m1a
= 600 – 10 × 20 = 400 N
(ii) When force F is applied to body B:
The equation of motion can be written as:
F – T = m2a
T = F – m2a
∴T = 600 – 20 × 20 = 200 N
APPEARS IN
RELATED QUESTIONS
The rear side of a truck is open and a box of 40 kg mass is placed 5 m away from the open end as shown in Figure. The coefficient of friction between the box and the surface below it is 0.15. On a straight road, the truck starts from rest and accelerates with 2 m s–2. At what distance from the starting point does the box fall off the truck? (Ignore the size of the box).
A car accelerates on a horizontal road due to the force exerted by.
The figure shows the displacement of a particle going along the X-axis as a function of time. The force acting on the particle is zero in the region
(a) AB
(b) BC
(c) CD
(d) DE
If the tension in the cable supporting an elevator is equal to the weight of the elevator, the elevator may be
(a) going up with increasing speed
(b) going down with increasing speed
(c) going up with uniform speed
(d) going down with uniform speed
Two blocks of equal mass m are tied to each other through a light string. One of the blocks is pulled along the line joining them with a constant force F. Find the tension in the string joining the blocks.
Two blocks A and B of mass mA and mB , respectively, are kept in contact on a frictionless table. The experimenter pushes block A from behind, so that the blocks accelerate. If block A exerts force F on block B, what is the force exerted by the experimenter on block A?
A man has fallen into a ditch of width d and two of his friends are slowly pulling him out using a light rope and two fixed pulleys as shown in the following figure. Show that the force (assumed equal for both the friends) exerted by each friend on the road increases as the man moves up. Find the force when the man is at a depth h.
Find the acceleration of the block of mass M in the situation shown in the following figure. All the surfaces are frictionless and the pulleys and the string are light.
State Newton's second law of motion. Under what condition does it take the form F = ma?
Use Newton's second law of motion to explain the following instance :
An athlete prefers to land on sand instead of hard floor while taking a high jump .
State the magnitude and direction of the force of gravity acting on the body of mass 5 kg. Take g = 9.8 m s-2.
State two factors which determine the momentum of a body.
Name the physical entity used for quantifying the motion of a body.
Name the physical quantity which equals the rate of change of linear momentum.
A stone is dropped from a cliff 98 m high.
What will be its speed when it strikes the ground?
A ball is thrown upward and reaches a maximum height of 19.6 m. Find its initial speed?
A metre scale is moving with uniform velocity. This implies ______.
A hockey player is moving northward and suddenly turns westward with the same speed to avoid an opponent. The force that acts on the player is ______.
Why is catching a slow-moving ball easier than catching a fast-moving ball?
