Question:
A bob is whirled in a horizontal circle by means of a string at an initial speed of 10 rpm. If the tension in the string is quadrupled while keeping the radius constant, the new speed is:
A bob is whirled in a horizontal circle by means of a string at an initial speed of 10 rpm. If the tension in the string is quadrupled while keeping the radius constant, the new speed is:
Updated On: Apr 30, 2025
- 20 rpm
- 40 rpm
- 5 rpm
- 10 rpm
Hide Solution
Verified By Collegedunia
The Correct Option is A
Solution and Explanation
Tension (T) provides the centripetal force: T = mv2/r. With r and m constant, T ∝ v2. If
T2 = 4T1, then v22 = 4v12.
Given v1 = 10 rpm, then v2 = √4 × 102 = 20 rpm.
Was this answer helpful?
1
0
Top Questions on Circular motion
- A body of mass 100 g is moving in a circular path of radius 2 m on a vertical plane as shown in the figure. The velocity of the body at point A is 10 m/s. The ratio of its kinetic energies at point B and C is: (Take acceleration due to gravity as 10 m/s\(^2\))
- JEE Main - 2025
- Physics
- Circular motion
- A wheel is rolling on a plane surface. The speed of a particle on the highest point of the rim is 8 m/s. The speed of the particle on the rim of the wheel at the same level as the center of the wheel, will be:
- JEE Main - 2025
- Physics
- Circular motion
- A body of mass 500 gram is rotating in a vertical circle of radius 1 m. What is the difference in its kinetic energies at the top and the bottom of the circle?
- UPCATET - 2025
- Physics
- Circular motion
- The angle between centripetal acceleration and tangential acceleration is.
- UPCATET - 2025
- Physics
- Circular motion
- A vehicle moves on a banked curve of radius \( r \) with banking angle \( \theta \). What is the speed \( v \) of the vehicle to avoid slipping without friction?
- CUET (UG) - 2025
- Physics
- Circular motion
View More Questions
Questions Asked in NEET exam
The output (Y) of the given logic implementation is similar to the output of an/a …………. gate.
- NEET (UG) - 2025
- Logic gates
- Two identical point masses P and Q, suspended from two separate massless springs of spring constants \(k_1\) and \(k_2\), respectively, oscillate vertically. If their maximum velocities are the same, the ratio of the amplitude of P to the amplitude of Q is :
- NEET (UG) - 2025
- Waves and Oscillations
- A particle of mass \(m\) is moving around the origin with a constant speed \(v\) along a circular path of radius \(R\). When the particle is at \( (0, R) \), its velocity is \( \mathbf{v} = -v \hat{\mathbf{i}} \). The angular momentum of the particle with respect to the origin is :
- NEET (UG) - 2025
- The Angular Momentum
- The radius of Martian orbit around the Sun is about 1.5 times the radius of the orbit of Mercury. The Martian year is 687 Earth days. Then which of the following is the length of 1 year on Mercury?
- NEET (UG) - 2025
- Kepler’s laws
- A balloon is made of a material of surface tension S and has a small outlet. It is filled with air of density \( \rho \). Initially the balloon is a sphere of radius R. When the gas is allowed to flow out slowly at a constant rate, its radius shrinks as \( r(t) \). Assume that the pressure inside the balloon is \( P(r) \) and is more than the outside pressure (\( P_0 \)) by an amount proportional to the surface tension and inversely proportional to the radius. The balloon bursts when its radius reaches \( r_0 \). Then the speed of gas coming out of the balloon at \( r = R \) is :
- NEET (UG) - 2025
- Surface Tension
View More Questions