Back to WORK-ENERGY-POWER
JEE PHYSICS MCQ: WORK-ENERGY-POWER
1
Medium
1 of 1
Application
+4 | -1
A man is supported on a frictionless horizontal surface. It is attached to a string and rotates about a fixed centre at an angular velocity . The tension in the string if F. If the length of string and angular velocity are doubled, the tension is string is now
View answer and explanation
Correct option: D
8 F
Option D (8 F) is correct because when both the length of the string and angular velocity are doubled, the tension becomes 8 times the original tension.
More Questions from WORK-ENERGY-POWER
Practice All Chapter MCQs →
A ball throwing cannon, lifts ball and throws with Speed. If balls are raised upto . then find Input power of cannon if it lifts 8 balls per minute and its efficiency is . Mass of each ball is .
Assertion:When a particle moves in a circle with a uniform speed its acceleration is constant but the velocity changes.
Reason: Angular displacement is not an axial vector. A body of mass thrown vertically upwards attains a maximum height . As what height will its kinetic energy be of its initial value? Assertion: Centripetal force does no work.
Reason: Force and displacement are perpendicular to each other. Statement I: Both stretched and compressed springs possess potential energy.
Statement II: Work done against restoring force is stored as potential energy. A bullet of mass moving at a speed hits a ball of mass kept at rest. A small part having mass breaks from the ball and sticks to the bullet. The remaining ball is found to move at a speed in the direction of the bullet. Find the velocity of the bullet after the collision.
Reason: Angular displacement is not an axial vector. A body of mass thrown vertically upwards attains a maximum height . As what height will its kinetic energy be of its initial value? Assertion: Centripetal force does no work.
Reason: Force and displacement are perpendicular to each other. Statement I: Both stretched and compressed springs possess potential energy.
Statement II: Work done against restoring force is stored as potential energy. A bullet of mass moving at a speed hits a ball of mass kept at rest. A small part having mass breaks from the ball and sticks to the bullet. The remaining ball is found to move at a speed in the direction of the bullet. Find the velocity of the bullet after the collision.