# Tension in a String

## Trending Questions

**Q.**In Youngs double slit experiment, how many maximas can be obtained on a screen (including the central maximum) on both sides of the central fringe if λ=2000 Angstrom and d=7000 Angstrom

**Q.**

A pendulum bob of mass 80 mg and carrying a charge of 2×10−8C is at rest in a uniform horizontal electric field of 20kVm−1 Find the tension in the thread.

**Q.**Find the reading of the spring balance considering spring, pulley and string to be massless.

- 600 N
- 300 N
- 400 N
- 200 N

**Q.**Three blocks of masses m1, m2 and m3 are connected by massless strings as shown in the figure and placed on a frictionless table. They are pulled with a force T3=40 N. The tension T2 will be: (Given m1= 10 kg, m2=6 kg and m3=4 kg)

- 20 N
- 40 N
- 10 N
- 32 N

**Q.**A string of negligible mass going over a clamped pulley of mass m supports a block of mass M as shown in the figure. The force on the pulley by the clamp is

- √2 Mg
- √2 mg
- g√(M−m)2+m2
- g√(M+m)2+M2

**Q.**A pendulum bob of mass 40 mg and carrying a charge of 2×10−8 C is at rest in a horizontal uniform electric field of 2×107 Vm−1. Calculate the tension in the thread of the pendulum and the angle it makes with the vertical.

- θ=45∘, T=√32×10−1 N
- θ=45∘, T=√8×10−1 N
- θ=30∘, T=√32×10−1 N
- θ=30∘, T=√8×10−1 N

**Q.**A block of mass 10 kg is suspended by three strings as shown in the figure. The tension T2 is (Take g=10m/s2)

- 100 N
- 100√3 N
- 50√3 N
- 100√3 N

**Q.**A mass m is suspended by a rope from a rigid support at P as shown in the figure. Another rope is tied at the end Q which is pulled horizontally with a force F. If the rope PQ makes angle θ with the vertical, then tension in the string PQ is

- Fsinθ
- Fcosθ
- Fsinθ
- Fcosθ

**Q.**Two bodies of mass 4 kg and 6 kg are attached to the ends of a string passing over a pulley. The 4 kg mass is attached to the table top by another string. The tension in this string T1 is equal to (take g=10 m/s2)

- 10 N
- 10.6 N
- 25 N
- 20 N

**Q.**

A body of mass m is suspended by two strings making angles α and β with the horizontal (as shown in the figure). Find the tensions in the strings?

T2=gcosβsin(α+β);T2=gcosαsin(α+β)

T2=mgcosαsin(α+β);T2=mgcosβsin(α+β)

T1=mgcosβsin(α+β);T2=mgcosαsin(α+β)

T2=mgcotα;T2=mgtanβ

**Q.**A solid horizontal surface is covered with a thin layer of oil. A rectangular block of mass m=0.4 kg is at rest on this surface. An impulse of 1.0 N s is applied to the block at time to t=0 so that it starts moving along the x-axis with a velocity v(t)=v0e−tτ, where v0 is a constant and τ=4 s. The displacement of the block, in metres, at t=τ is

[Take e−1=0.37]

**Q.**A light rod is hinged (free to rotate) at its centre O as shown in figure. Two point charges of same magnitude +q are kept at its two ends. Rod is placed in uniform electric field E as shown. Space is gravity free. Net torque about the hinge is

- 2rqE
- 4rqE
- 3rqE
- Zero

**Q.**A force of F=(5y+20)^j N acts on a particle. The work done by this force when the particle is moved from y=0 m to y=10 m is ______J.

**Q.**Two blocks, each having a mass M, rest on frictionless surfaces as shown in the figure. If the pulleys are light and frictionless, and M on the incline is allowed to move down along the incline, then the tension in the string will be

- 23Mgsinθ
- 32Mgsinθ
- Mgsinθ2
- 2Mgsinθ

**Q.**A flexible chain of mass m hangs between two fixed points A and B at the same level. The inclination of the chain with the horizontal at the two points of support is θ. The tension at the midpoint C of the chain is

- mgtanθ
- mg2tanθ
- Zero
- (mg)(sinθ+cosθ2)

**Q.**What is the minimum value of F needed so that block begins to move upward on frictionless incline plane as shown?

- Mgtan(θ2)
- Mgcot(θ2)
- Mgsinθ(1+sinθ)
- Mgsin(θ2)

**Q.**A string of length 1 m is fixed at one end and carries a mass of 100 g at the other end. The string makes (2/π) revolutions per second around vertical axis through the fixed end. What is the tension in the string :-

- 1.6 N
- 0.8 N
- 3.2 N
- 2.4 N

**Q.**A ball is held at rest in position A by two light cords. The horizontal cord is now cut and the ball swings to position B. What is the ratio of the tension in the cord at position B to that at position A originally?

- 1/2
- 1
- 3
- 3/4

**Q.**One end of a massless rope, which passes over a massless and frictionless pulley P is tied to a hook C while the other end is free. Maximum tension that the rope can bear is 840 N. With what value of maximum safe acceleration (in ms−2) can a man of 60 kg climb on the rope?

- 16
- 6
- 4
- 8

**Q.**Two blocks of mass 5 kg and 3 kg are tied with a heavy rope of mass 2 kg. An external force of 200 N is applied on 5 kg block and the whole system accelerates upwards. Find the tension at the midpoint of the rope?

(Take g= 10 m/s2)

- 80 N
- 120 N
- 100 N
- 60 N

**Q.**

Two blocks of masses 2.9 kg and 1.9 kg are suspended from a rigid support by two inextensible wires each of length 1 m, the upper wire has negligible mass and the lower wire has a uniform mass of 0.2 kg/m. The whole system of block, wire and support has an upward acceleration of 0.2 m/s2. (take g=9.8m/sec2)

The tension at the mid-point of lower wire is:

- 20 N
- 20.4 N
- 10.4 N
- 30 N

**Q.**

An object is resting at the bottom of two strings which are inclined at an angle of 120∘ with each other. Each string can withstand a tension of 20 N. The maximum weight of the object that can be sustained without breaking the strings is

- 10 N
- 20 N
- 20√2 N
- 40 N

**Q.**A rope of mass 5 kg is moving vertically with an upward force of 100 N acting at the upper end and a downward force of 70 N acting at the lower end. The tension at the midpoint of the rope is

(Take g=10 m/s2)

- 100 N
- 85 N
- 75 N
- 105 N

**Q.**Two blocks of masses 6 kg and 4 kg connected by a rope of mass 2 kg are resting on a frictionless floor as shown in the figure. If a constant force 60 N is applied to the 6 kg block, find the tension in the rope at points A, B and C. B is at the mid-point and points A and C are at the ends. Assume that the mass of the rope is uniformly distributed along its length.

- None of the above
- 30 N, 25 N, 20 N respectively
- 20 N, 20 N, 30 N respectively
- 30 N, 20 N, 25 N respectively

**Q.**A body of mass 5 kg is suspended by the strings making angles 60o and 30o with the horizontal as shown in the figure. Find the tension in the strings. (g=10 m/s2 )

- T1=25 N & T2=25 N
- T1=25√3 N & T2=25 N
- T1=25 N & T2=25√3 N
- T1=25√3 N & T2=25√3 N

**Q.**A 10 kg monkey is climbing a massless rope attached to a 15 kg mass over a smooth tree limb. The mass is lying on the ground. In order to raise the mass from the ground he must climb with:

- Acceleration greater than 5 m/sec2
- Acceleration greater than 2.5 m/sec2
- High speed
- Acceleration greater than 10 m/sec2

**Q.**Study the v−t graph given here, plotted for a particle of mass 50 g. In which period will it have the maximum force?

- P
- Q
- R
- None of these

**Q.**

In a game of tug of war, a condition of equilibrium exists. Both the teams pull the rope with a force of 10^{4} N. Find the tension in the rope.

${10}^{4}N$

${10}^{5}N$

$0N$

$2\times {10}^{4}N$

**Q.**In the arrangement as shown, tension T2 is (g=10 m/s2)

- 50 N
- 100 N
- 50√3 N
- 100√3 N

**Q.**

An object of mass 0.5 kg is whirled at the end of a string 0.8 m long. If the string makes three revolutions in 1.2 sec, find the tension on the string.