Bissoy.com
Doctors Medicines MCQs Q&A

A uniform rod of length 1 m is pivoted at its midpoint. If the weight of 40 gf is suspended at one of its ends. Where should the weight of 120 gf be suspended to keep the rod horizontal?

A uniform rod of length 1 m is pivoted at its midpoint. If the weight of 40 gf is suspended at one of its ends. Where should the weight of 120 gf be suspended to keep the rod horizontal? Correct Answer 16 cm from the midpoint

The correct answer is option 1) i.e. 16 cm from the midpoint

CONCEPT:

  • Equilibrium is a condition when the body is not undergoing a change in rotational or translational motion.
  • The conditions for equilibrium of a body are as follows:
    1. The algebraic sum of the forces must be zero.
    2. The algebraic sum of the moments of the forces about any point in their plane must be zero.
CALCULATION:
  • Let us assume 100 gf is located at distance x from the pivoted point.​
  • If the rod has to stay horizontal, the system must be in equilibrium.
  • Therefore, the algebraic sum of the moments of the forces about the pivoted point must be zero.

ΣM = 0

⇒ 40(0.5) - 120(x) = 0

⇒ 20 = 120x 

⇒ x = 0.16 cm

  • Therefore, the weight of 120 gf must be suspended 16 cm from the midpoint.

Related Questions

A uniform rod 9 m long weighing 40 kg is pivoted at a point 2 m from one end where a weight of 120 kg is suspended. The required force acting at the end in a direction perpendicular to rod to keep it equilibrium, at an inclination 60° with horizontal, is
A hollow rod has frictionless inner walls. Inside the rod are two small spheres that are kept on either side of the centre of rod. The rod is rotated about its central axis which is perpendicular to the plane of rotation. If the rod had been rotated by an impulsive torque which gave it an instantaneous angular velocity of 5rad/s, what will be the angular velocity after some finite but long time ‘t’? Assume no external forces act on rod after the impulse. Also state what will happen to the spheres in the centre of the rod. The rod has a mass =2kg & length =10cm. The two spheres have a mass =1kg each.
A square ABCD, L is the midpoint of side AB, M is the midpoint of side BC, N is the midpoint of side CD and O is the midpoint of side AD, then find the ratio of area of shaded region PQRS to the area of square ABCD.
What is the condition for a tree to be weight balanced. where a is factor and n is a node? >= a*weight and weight >= a*weight. b) weight >= a*weight and weight >= a*weight. c) weight >= a*weight and weight >= a*weight. d) weight is a non zero
A rod of length L with uniform charge density $$\lambda $$ per unit length is in the XY-plane and rotating about Z-axis passing through one of its edge with an angularvelocity $$\overrightarrow \omega $$ as shown in the figure below. $$\left( {{\bf{\hat r}},\,\hat \phi ,\,{\bf{\hat z}}} \right)$$   refer to the unit vectors at Q, $$\overrightarrow {\bf{A}} $$ is the vector potential at a distance d from the origin O along Z-axis for d ≪ L and $$\overrightarrow {\bf{J}} $$ is the current density due to the motion of the rod. Which one of the following statements is correct?
Electromagnetic Theory mcq question image
A small connecting rod of mass 1.5 kg is suspended in a horizontal plane by two wires 1.25 m long. The wires are attached to the rod at points 120 mm on either side of the centre of gravity. If the rod makes 20 oscillations in 40 seconds, find the radius of gyration of the rod about a vertical axis through the centre of gravity.
A small connecting rod of mass 1.5 kg is suspended in a horizontal plane by two wires 1.25 m long. The wires are attached to the rod at points 120 mm on either side of the centre of gravity. If the rod makes 20 oscillations in 40 seconds, find the mass moment of inertia of the rod about a vertical axis through the centre of gravity.
The following coding system shows the letter codes for numbers. Excluding the exceptions mentioned below, the digits in the question are to be transformed into letter codes as follows: Digit 0 1 2 3 4 5 6 7 8 9 Letter Code A B C D E F G H I J Exceptions: i. If a number begins with a nonzero even digit, that digit should be coded as N. ii. If a number begins with a nonzero odd digit, that digit should be coded as P. iii. If a number begins and also ends with non-zero even digits, those two digits at the extreme ends should be coded as Q. iv. If a number begins and also ends with nonzero odd digits, those two digits at the extreme ends should be coded as W. v. If a number's middle digit is a multiple of 2 that digit should be coded as Z. Barring these exceptions, the other digits should be codified as per the above-mentioned letter codes. Find the appropriate code for the following number-group 3214067
Among five rods, P, Q, R, S and T, the weight of T is 20 kg. The weight of S is half the weight of P. The weight of Q is one-fourth the weight of P. R's weight is twice the weight of Q. The weight of P is twice the weight of T. Which rod is the lightest among all?
Weight of Arun is 4/7 of the weight of Bablu. Weight of Bablu is 1/2 of the weight of Ram. Weight of Ram is 4 times of the weight of Deep. Weight of Deepis 1/9 of the weight of Ankit. Whose weight is more than the weight of Deep but less than the weight of Bablu?