Advertisements
Advertisements
प्रश्न
Two bodies having equal masses are moving with uniform speeds of v and 2v respectively. Find the ratio of their kinetic energies.
Advertisements
उत्तर
Let the masses of the two bodies be (m1) = m kg and (m2) = m kg .
Velocity of the first body, (v1) = v m/s
Velocity of the first body, (v2) = 2v m/s
The required ratio is-
= `"(Kinetic energy)"_1/"(Kinetic energy)"_2`
= `(1/2 (m_1)(v_1)^2)/(1/2 (m_2)(v_2)^2)`
So put the values to get ,
= `(1)^2/(2)^2`
= `1/4`
The ratio of K.E is, K.E of body 1 : K.E of body 2 = 1 : 4.
APPEARS IN
संबंधित प्रश्न
A ball is placed on a compressed spring. What form of energy does the spring possess? On releasing the spring, the ball flies away. Give a reason.
Fill in the blank with suitable word :
The ability of a body to do work is called __________. The ability of a body to do work because of its motion is called __________.
What type of energy is possessed : by the piece of stone which is thrown away on releasing the stretched rubber strings of catapult?
An iron sphere of mass 10 kg has the same diameter as an aluminium sphere of mass 3.5 kg. Both the spheres are dropped simultaneously from a tower. When they are 10 m above the ground, they have the same :
Name the device or machine which convert :
Chemical energy into electrical energy.
Name the device or machine which convert :
Heat energy into kinetic energy (or mechanical energy).
When an object falls freely towards the earth, then its total energy :
How much energy does a 100 W electric bulb transfer in 1 minute?
An automobile engine propels a 1000 kg car (A) along a levelled road at a speed of 36 km h–1. Find the power if the opposing frictional force is 100 N. Now, suppose after travelling a distance of 200 m, this car collides with another stationary car (B) of the same mass and comes to rest. Let its engine also stop at the same time. Now the car (B) starts moving on the same level road without getting its engine started. Find the speed of the car (B) just after the collision.
A body of mass 10 kg at rest is acted upon simultaneously by two forces 4 N and 3 N at right angles to each other. The kinetic energy of the body at the end of 10 s is
