The kinetic energy of a body becomes four times its initial value. The new linear momentum will be
- twice the initial value
- same as the initial value
- four times the initial value
- thrice the initial vlaue
The Correct Option is A
Solution and Explanation
Top Questions on work, energy and power
- Two heaters A and B have power rating of 1 kW and 2 kW, respectively. Those two are first connected in series and then in parallel to a fixed power source. The ratio of power outputs for these two cases is :
- NEET (UG) - 2024
- Physics
- work, energy and power
- At any instant of time t, the displacement of any particle is given by 2t – 1 (SI unit) under the influence of force of 5N. The value of instantaneous power is (in SI unit):
- NEET (UG) - 2024
- Physics
- work, energy and power
- The temperatures of two bodies differ by 1°C. How much will they differ on Fahrenheit scale?
- OJEE - 2024
- Physics
- work, energy and power
- Same quantity of ice is filled in each of the two identical metal containers P and Q having the same size and shape but of different materials. In P ice melts completely in time \( t_1 \), whereas in Q the time taken is \( t_2 \). Then the ratio of conductivities of P and Q is:
- OJEE - 2024
- Physics
- work, energy and power
- A block falls from a table 0.6 m high. It lands on an ideal, mass-less, vertical spring with a force constant of 2.4 kN/m. The spring is initially 25 cm high, but it is compressed to a minimum height of 10 cm before the block is stopped. Find the mass of the block (g = 9.81 m/s\(^2\)):
- OJEE - 2024
- Physics
- work, energy and power
Questions Asked in KCET exam
- The electric current flowing through a given conductor varies with time as shown in the graph below. The number of free electrons which flow through a given cross-section of the conductor in the time interval \( 0 \leq t \leq 20 \, \text{s} \) is
- KCET - 2024
- Current electricity
- Auxins : Apical dominance : : Gibberellins : .............
- KCET - 2024
- Plant Physiology
- A die is thrown 10 times. The probability that an odd number will come up at least once is:
- KCET - 2024
- Probability
- The incorrect statement about the Hall-Heroult process is:
- KCET - 2024
- General Principles and Processes of Isolation of Elements
- Corner points of the feasible region for an LPP are $(0, 2), (3, 0), (6, 0), (6, 8)$ and $(0, 5)$. Let $z = 4x + 6y$ be the objective function. The minimum value of $z$ occurs at:
- KCET - 2024
- Linear Programming Problem
Concepts Used:
Power
Power is the rate of doing an activity or work in the minimum possible time. It is the amount of energy transferred or converted per unit of time where large power means a large amount of work or energy.
For example, when a powerful car accelerates speedily, it does a large amount of work which means it exhausts large amounts of fuel in a short time.
The formula of Power:
Power is defined as the rate at which work is done upon an object. Power is a time-based quantity. Which is related to how fast a job is done. The formula for power is mentioned below.
Power = Work / time
P = W / t
Unit of Power:
As power doesn’t have any direction, it is a scalar quantity. The SI unit of power is Joules per Second (J/s), which is termed as Watt. Watt can be defined as the power needed to do one joule of work in one second.