Question
Can normal force do a nonzero work on an object. If yes, give an example. If no, give reason.
✓
Answer
Yes. Let us consider an elevator accelerating upward with a body placed in it. In this case, the normal reaction offered by the floor of the elevator on the body is greater than the weight of the body acting in the downward direction. If a person is observing this from the ground, then, for him, the normal reaction is doing a positive work, as the elevator is moving upward.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
Two particles located at a point begin to move with velocities $4m s^{-1}$ and $1m s^{-1}$ horizontally in opposite directions. Determine the time when their velocity vectors become perpendicular. Assume that the motion takes place in a uniform gravitational field of strength g.
→Consider the situation shown in figure. What are the signs of $q_1$ and $q_2$? If the lines are drawn in proportion to the charge, what is the ratio $\frac{\text{q}_1}{\text{q}_2}?$
→A block of 2kg is suspended from the ceiling through a massless spring of spring constant k = 100N/m. What is the elongation of the spring? If another 1kg is added to the block, what would be the further elongation?
The time period of a mass hanging from an ideal spring is 2 seconds. If along with it 2 kg if the mass is added and the time period becomes 3 seconds find the value of $m$.
→Explain the pressure exerted by an ideal gas and also find the average kinetic energy per molecule of the gas.
Consider that an ideal gas ( $n$ moles) is expanding in a process given by $p=f(V)$, which passes through a point $\left(V_0\right.$, $\left.p_0\right)$. Show that the gas is absorbing heat at $\left(P_0, V_0\right)$, if the slope of the curve $p=f(V)$ is larger than the slope of the adiabat passing through $\left(\mathrm{P}_0, \mathrm{~V}_0\right)$.
→It is a common observation that rain clouds can be at about a kilometre altitude above the ground.
Estimate the order of magnitude force on umbrella. Typical lateral separation between two rain drops is 5cm. (Assume that umbrella is circular and has a diameter of 1m and cloth is not pierced through !!)
Estimate the order of magnitude force on umbrella. Typical lateral separation between two rain drops is 5cm. (Assume that umbrella is circular and has a diameter of 1m and cloth is not pierced through !!)
The radius of curvature of a concave mirror, measured by a spherometer is given by: $\text{R}=\frac{\text{l}^2}{6\text{h}}+\frac{\text{h}}{2}$ The value of l and h are 4.0cm and 0.065cm respectively where l is measured by a metre scale and h by the spherometer. Find the relative error in the measurement of R.
→An open pipe is suddenly closed at one end with the result that the frequency of sound harmonic of the closed pipe is found to be higher by 100Hz than the fundamental frequency of the open pipe. Calculate the fundamental frequency of the open pipe.
A transformer has 50 turns in the primary and 100 in the secondary. If the primary is connected to a 220V DC supply, what will be the voltage across the secondary?