NEET PYQs for Speed and Velocity with Solutions: Practice NEET Previous Year Questions

1.

A small sphere of radius ‘r’ falls from rest in a viscous liquid. As a result, heat is produced due to viscous force. The rate of production of heat when the sphere attains its terminal velocity, is proportional to

• r³
• r⁵
• r²
• r⁴

2.

Two cars $P$ and $Q$ start from a point at the same time in a straight line and their positions are represented by $x _{ P }( t )= at + bt ^{2}$ and $x _{ Q }( t )=f t - t ^{2}$. At what time do the cars have the same velocity ?

• $\frac{a - f}{1 + b}$
• $\frac{a + f}{2( b - 1)}$
• $\frac{a + f}{2( 1 + b)}$
• $\frac{f - a }{2( 1 + b)}$

3.

A person travelling in a straight line moves with a constant velocity v1 for certain distance 'x' and with a constant velocity $v_2$ for next equal distance. The average velocity v is given by the relation

• $\frac{1}{v}=\frac{1}{v_{1}}+\frac{1}{v_{2}}$
• $\frac{2}{v}=\frac{1}{v_{1}}+\frac{1}{v_{2}}$
• $\frac{v}{2}=\frac{v_{1}+v_{2}}{2}$
• $v=\sqrt{v_{1}v_{2}}$

4.

A wheel of a bullock cart is rolling on a level road, as shown in the figure below. If its linear speed is v in the direction shown, which one of the following options is correct (P and Q are any highest and lowest points on the wheel, respectively) ?
 

• Point P moves slower than point Q.
• Point P moves faster than point Q
• Both the points P and Q move with equal speed.
• Point P has zero speed.

5.

The position $x$ of a particle with respect to time t along $x$ -axis is given by $x = 9t^2-t^3$ where $x$ is in metres and $t$ in seconds. What will be the position of this particle when it achieves maximum speed along the $+x$ direction?

• 54 m
• 81 m
• 24 m
• 32 m

6.

At what temperature will the rms speed of oxygen molecules become just sufficient for escaping from the Earth's atmosphere ?
(Given : Mass of oxygen molecule (m) = 2.76×10^-26 kg
Boltzmann's constant k_B = 1.38×10^-23 J K^-1)

• 2.508×10⁴ K
• 5.016×10⁴ K
• 8.360×10⁴ K
• 1.254×10⁴ K

7.

An electron of mass m with an initial velocity \(\overrightarrow{V} = V_0 \hat{i} (V_0 \gt 0)\) enters an electric field \(\overrightarrow{E} = -E_0 \;\hat{i} (E_0=constant  \gt 0)\) at t = 0. If \(\lambda_0\) is its de-Broglie wavelength initially, then its de-Broglie wavelength at time t is

• \(\frac{\lambda_0}{\left(1+\frac{eE_0}{mV_0}t\right)}\)
• \(\lambda_0t\)
• \(\lambda_0\left(1+\frac{eE_0}{mV_0}t\right)\)
• \(\lambda_0\)

8.

The velocity (v) - time (t) plot of the motion of a body is shown below :
 

The acceleration (a) - time(t) graph that best suits this motion is :