Question:
If the kinetic energy of a moving body reduces to \(49\%\), then its velocity is reduced to
If the kinetic energy of a moving body reduces to \(49\%\), then its velocity is reduced to
Show Hint
If KE becomes \(k\) times, velocity becomes \(\sqrt{k}\) times.
Updated On: Apr 24, 2026
- \(49\%\)
- \(70\%\)
- \(30\%\)
- \(25\%\)
- \(51\%\)
Show Solution
Verified By Collegedunia
The Correct Option is B
Solution and Explanation
Step 1: Understanding the Concept:
Kinetic energy \(KE = \frac{1}{2}mv^2\). So \(KE \propto v^2\).
Step 2: Detailed Explanation:
\(\frac{KE_2}{KE_1} = \frac{49}{100} = 0.49\)
\(\frac{v_2^2}{v_1^2} = 0.49 \Rightarrow \frac{v_2}{v_1} = \sqrt{0.49} = 0.7 = 70\%\)
Step 3: Final Answer:
Velocity is reduced to \(70\%\).
Kinetic energy \(KE = \frac{1}{2}mv^2\). So \(KE \propto v^2\).
Step 2: Detailed Explanation:
\(\frac{KE_2}{KE_1} = \frac{49}{100} = 0.49\)
\(\frac{v_2^2}{v_1^2} = 0.49 \Rightarrow \frac{v_2}{v_1} = \sqrt{0.49} = 0.7 = 70\%\)
Step 3: Final Answer:
Velocity is reduced to \(70\%\).
Was this answer helpful?
0
0
Top KEAM Physics Questions
- A body oscillates with SHM according to the equation (in SI units), $x = 5 cos \left(2\pi t +\frac{\pi}{4}\right) .$ Its instantaneous displacement at $t = 1$ second is
Kepler's second law (law of areas) of planetary motion leads to law of conservation of
- Two capillary tubes A and B of diameter $1\, mm$ and $2\, mm$ respectively are dipped vertically in a liquid. If the capillary rise in A is 6 cm, then the capillary rise in B is
- In the circuit given in figure, 1 and 2 are ammeters. Just after key K is pressed to complete the circuit, the reading will be
- A plate has a length $ 5\pm 0.1\text{ }cm $ and breadth $ 2\pm 0.01\text{ }cm $ . Then the area of the plate is:
View More Questions
Top KEAM work, energy and power Questions
- A spring stores $1\,J$ of energy for a compression of $1\,mm$. The additional work to be done to compress it further by $1\,mm$ is
- According to the work-energy theorem, the work done by the net force on a particle is equal to the change in its
- An electric pump is used to fill an overhead tank of capacity $ 9\,{{m}^{3}} $ kept at a height of $ 10\, m $ above the ground. If the pump takes $ 5 \,min $ to fill the tank by consuming $ 10 \,kW $ power the efficiency of the pump should be (Take $ g=10\text{ }m{{s}^{-2}} $ )
- A ball dropped from a height of $2\,m$ rebounds to a height of $1.5\,m$ after hitting the ground. Then the percentage of energy lost is
- A ball is dropped from a height $h$. If the coefficient of restitution is $e$ then to what height will it rise after jumping twice from the ground
View More Questions
Top KEAM Questions
- i.$\quad$ They help in respiration ii.$\quad$ They help in cell wall formation iii.$\quad$ They help in DNA replication iv. $\quad$They increase surface area of plasma membrane Which of the following prokaryotic structures has all the above roles?
- A body oscillates with SHM according to the equation (in SI units), $x = 5 cos \left(2\pi t +\frac{\pi}{4}\right) .$ Its instantaneous displacement at $t = 1$ second is
- The pH of a solution obtained by mixing 60 mL of 0.1 M BaOH solution at 40m of 0.15m HCI solution is
Kepler's second law (law of areas) of planetary motion leads to law of conservation of
- If $\int e^{2x}f' \left(x\right)dx =g \left(x\right)$, then $ \int\left(e^{2x}f\left(x\right) + e^{2x} f' \left(x\right)\right)dx =$
View More Questions