KCET · Physics · Work Power Energy
A body of mass 0.25 kg travels along a straight line from \(\mathrm{x}=0\) to \(\mathrm{x}=2 \mathrm{~m}\) with a speed \(\mathrm{v}=\mathrm{k} \mathrm{x}^{3 / 2}\) where k \(=2\) SI units. The work done by the net during this displacement is
- A 8 J
- B 16 J
- C 32 J
- D 4 J
Answer & Solution
Correct Answer
(D) 4 J
Step-by-step Solution
Detailed explanation
\(\begin{aligned} & \mathrm{W}_{\text {net }}=\Delta \mathrm{KE} \\ & =\frac{1}{2} \mathrm{mv}^2-\frac{1}{2} \mathrm{mu}^2 \\ & =\frac{1}{2} \times 0.25\left(\mathrm{k}(2)^{3 / 2}\right)^2-0 \\ & =\frac{1}{2} \times 0.25 \times 2^2 \times 2^3 \\ & =4 \mathrm{~J}\end{aligned}\)
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Physics
- The centre of mass of an extended body on the surface of the earth and its centre of gravityKCET 2022 Easy
- In the A.C. circuit shown, keeping ' \( K \) ' pressed, if an iron rod is inserted into the coil, the bulb in
the circuit,
KCET 2017 Easy - In the figure shown, the conductor PQ of length \(l\) is moved from \(x = 0\) to \(x = b\) and then up to \(x = 2b\) with a constant velocity \(\vec{v}\). A uniform magnetic field \(\vec{B}\) is perpendicular to the plane of the paper and extends from \(x = 0\) to \(x = b\) and it is zero from \(x > b\). The magnitude of emf Induced in the conductor is
KCET 2026 Easy - In the circuit given here, the points A, B and \(C\) are \(70 \mathrm{~V}\), zero, \(10 \mathrm{~V}\) respectively. Then
KCET 2010 Medium - The photoelectric work function for photo metal is 2.4 eV . Among the four wavelengths, the wavelength of light for which photoemission does not take place isKCET 2024 Easy
- The surface temperature of the sun which has maximum energy emission at \(500 \mathrm{~nm}\) is \(6000 \mathrm{~K}\). The temperature of a star which has maximum energy emission at \(400 \mathrm{~nm}\) will beKCET 2007 Easy
More PYQs from KCET
- \( \int_{-\frac{I}{2}}^{\frac{\pi}{2}} \frac{d x}{e^{\sin x}+1} \) is equal toKCET 2017 Easy
- How many chiral carbon atoms are present in \(2,3,4\)-trichloropentane?KCET 2007 Medium
- Ethanoic acid undergoes Hell-Volhard Zelinsky reaction but methanoic acid does not, because ofKCET 2022 Medium
- The temperature coefficient of a reaction is \( 2 \). When the temperature is increased from \( 30^{\circ} \mathrm{C} \) to
\( 90^{\circ} \mathrm{C} \), the rate of reaction is increased byKCET 2018 Hard - How many microsporangia are located at the corners of a typical bilobed anther of angiosperm?KCET 2021 Medium
- A body of mass \(5 \mathrm{~kg}\) is thrown vertically up with a kinetic energy of \(490 \mathrm{~J}\). The height at which the kinetic energy of the body becomes half of the original value is
(acceleration due to gravity \(=9.8 \mathrm{~ms}^{-2}\) )KCET 2011 Easy