JEE Mains · Physics · STD 11 - Motion in straight line
- JEE Mains 2026
- Hard
- MCQ
A particle starts moving from time \(t=0\) and its coordinate is given as \(x(t)=4t^{3}-3t.\)
A. The particle returns to its original position (origin) 0.866 units later
B. The particle is 1 unit away from origin at its turning point.
C. Acceleration of the particle is non-negative.
D. The particle is 0.5 units away from origin at its turning point.
E. Particle never turns back as acceleration is non-negative.
Choose the correct answer from the options given below :
Pick an option to check your answer.
Answer & Solution
Correct Answer
(B) A, B, C only
Step-by-step Solution
Detailed explanation
\(x=0\Rightarrow t=0,\frac{\sqrt{3}}{2}\)
\(v=12t^{2}-3\)
At turning point, \(v=0\)
\(t=\frac{1}{2}\Rightarrow x=\frac{4}{8}-\frac{3}{2}=-1\)
\(a=24t\) (always positive)
\(v=12t^{2}-3\)
At turning point, \(v=0\)
\(t=\frac{1}{2}\Rightarrow x=\frac{4}{8}-\frac{3}{2}=-1\)
\(a=24t\) (always positive)
More questions from Physics
- A prism of angle \(A=1^{\circ}\) has a refractive index \(\mu=1.5 .\) A good estimate for the minimum angle of deviation (in degrees) is close to \(N/10\) Value of \(N\) is......JEE Mains 2020 Medium
- A particle of mass \(\mathrm{m}\) and charge \(\mathrm{q}\) has an initial velocity \(\overline{\mathrm{v}}=\mathrm{v}_{0} \hat{\mathrm{j}} .\) If an electric field \(\overrightarrow{\mathrm{E}}=\mathrm{E}_{0} \hat{\mathrm{i}}\) and magnetic field \(\overrightarrow{\mathrm{B}}=\mathrm{B}_{0} \hat{\mathrm{i}}\) act on the particle, its speed will double after a time:JEE Mains 2020 Medium
- The mass and the diameter of a planet are three times the respective values for the Earth. The period of oscillation of a simple pendulum on the Earth is \(2\,s\). The period of oscillation of the same pendulum on the planet would beJEE Mains 2019 Hard
- Two equal capacitors are first connected in series and then in parallel. The ratio of the equivalent capacities in the two cases will beJEE Mains 2021 Medium
- A liquid drop having \(6\) excess electrons is kept stationary under a uniform electric field of \(25.5\, k\,Vm^{-1}\) . The density of liquid is \(1.26\times10^3\, kg\, m^{-3}\) . The radius of the drop is (neglect buoyancy)JEE Mains 2013 Hard
- A body \(A,\) of mass \(m=0.1\; kg\) has an initial velocity of \(3 \hat{\mathrm{i}}\; \mathrm{ms}^{-1} .\) It collides elastically with another body, \(\mathrm{B}\) of the same mass which has an initial velocity of \(5 \hat{\mathrm{j}} \;\mathrm{ms}^{-1}\). After collision. A moves with a velocity \(\overline{\mathrm{v}}=4(\hat{\mathrm{i}}+\hat{\mathrm{j}})\). The energy of \(\mathrm{B}\) after collision is written as \(\frac{\mathrm{x}}{10} \;\mathrm{J}\) The value of \(x\) isJEE Mains 2020 Medium
More PYQs from JEE Mains
- Two identical strings \(X\) and \(Z\) made of same material have tension \(T _{ x }\) and \(T _{ z }\) in them. If their fundamental frequencies are \(450\, Hz\) and \(300\, Hz ,\) respectively, then the ratio \(T _{ x } / T _{ z }\) is\(.....\)JEE Mains 2020 Easy
- A capacitor, \(C_1=6 \mu \mathrm{~F}\) is charged to a potential difference of \(\mathrm{V}_0=5 \mathrm{~V}\) using a 5 V battery. The battery is removed and another capacitor, \(\mathrm{C}_2=12 \mu \mathrm{~F}\) is inserted in place of the battery. When the switch 'S' is closed, the charge flows between the capacitors for some time until equilibrium condition is reached. What are the charges \(\left(q_1\right.\) and \(\left.q_2\right)\) on the capacitors \(C_1\) and \(C_2\) when equilibrium condition is reached.
JEE Mains 2025 Medium - If the maximum value of accelerating potential provided by a ratio frequency oscillator is \(12\, {kV}\). The number of revolution made by a proton in a cyclotron to achieve one sixth of the speed of light is ....... . \(\left[{m}_{{p}}=1.67 \times 10^{-27} {kg}, {e}=1.6 \times 10^{-19} {C},\right.\) Speed of light \(\left.=3 \times 10^{8} {m} / {s}\right]\)JEE Mains 2021 Hard
- An object is placed at a distance of \(12\,cm\) in front of a plane mirror. The virtual and erect image is formed by the mirror. Now the mirror is moved by \(4\,cm\) towards the stationary object. The distance by which the position of image would be shifted, will be:JEE Mains 2023 Medium
- A body of weight \(200 \mathrm{~N}\) is suspended form a tree branch thought a chain of mass \(10 \mathrm{~kg}\). The branch pulls the chain by a force equal to _______. (if \(g=10 \mathrm{~m} / \mathrm{s}^2\) )JEE Mains 2024 Hard
- Ten charges are placed on the circumference of a circle of radius \(R\) with constant angular separation between successive charges. Alternate charges \(1,3,5,7,9\) have charge \((+q)\) each, while \(2,4,6,8,10\) have charge \((-q)\) each. The potential \(V\) and the electric field \(E\) at the centre of the circle are respectively (Take \(V =0\) at infinity \()\)JEE Mains 2020 Hard