If momentum of an object is increased by 10% then its kinetic energy w...
It will be increased by 21%
Let the initial mass of the body be m and its velocity be v.
Initial momentum of the body = mv
Initial KE = mv^2/2
If the momentum increases by 10%, new momentum = mv + 10% of mv
= mv + 10/100mv
= mv + mv/10
=11mv/10
=m(11v/10)
New velocity = 11v/10
Increase in velocity = v/10
New KE = m(11v/10)^2/2
= 121/100mv^2/2
Increase in KE = 21%
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If momentum of an object is increased by 10% then its kinetic energy w...
If momentum of an object is increased by 10% then its kinetic energy w...
Momentum and Kinetic Energy
Momentum and kinetic energy are two important concepts in physics that describe the motion of an object. Momentum is a measure of an object's motion and is defined as the product of its mass and velocity. Kinetic energy, on the other hand, is the energy possessed by an object due to its motion and is given by the equation 1/2 * m * v^2, where m is the mass of the object and v is its velocity.
Relationship between Momentum and Kinetic Energy
There is a direct relationship between momentum and kinetic energy. When the momentum of an object changes, its kinetic energy also changes accordingly. The change in kinetic energy can be determined by considering the concept of work.
The Work-Energy Principle
According to the work-energy principle, the work done on an object is equal to the change in its kinetic energy. Mathematically, this can be expressed as:
Work = Change in Kinetic Energy
When a force is applied to an object, it does work on the object, exerting a force over a distance. This work transfers energy to the object, resulting in a change in its kinetic energy.
Increase in Momentum
If the momentum of an object is increased by 10%, it means that the object's mass or velocity, or both, have increased. Let's consider the two scenarios separately:
1. Increased Mass: If only the mass of the object is increased while its velocity remains constant, the momentum will increase but the kinetic energy will remain the same. This is because kinetic energy depends on the square of the velocity, not the mass.
2. Increased Velocity: If only the velocity of the object is increased while its mass remains constant, both the momentum and kinetic energy will increase. This is because kinetic energy depends on the square of the velocity, so an increase in velocity results in a greater change in kinetic energy compared to the change in momentum.
Conclusion
In conclusion, if the momentum of an object is increased by 10%, the change in its kinetic energy depends on whether the increase is due to an increase in mass, velocity, or both. If only the mass is increased, the kinetic energy remains the same. However, if the velocity is increased, both the momentum and kinetic energy will increase.