A meter scale is moving with uniform velocity. This impliesAThe force acting on the scale is zero, but a torque about the centre of mass can act on the scale.BThe force acting on the scale is zero and the net torque acting about the centre of mass of the scale is also zero.CThe total force acting on it need not be zero but the torque on it is zero.DNeither force nor the torque needs to be zero.
Question
A meter scale is moving with uniform velocity. This impliesAThe force acting on the scale is zero, but a torque about the centre of mass can act on the scale.BThe force acting on the scale is zero and the net torque acting about the centre of mass of the scale is also zero.CThe total force acting on it need not be zero but the torque on it is zero.DNeither force nor the torque needs to be zero.
Solution
The correct answer is B. The force acting on the scale is zero and the net torque acting about the centre of mass of the scale is also zero.
Here's why:
-
Newton's first law of motion states that an object will remain at rest or move in a straight line at a constant speed unless acted upon by an external force. So, if the meter scale is moving with a uniform velocity, it means there is no net external force acting on it. Hence, the force acting on the scale is zero.
-
Torque is a measure of how much a force acting on an object causes that object to rotate. The object will continue to rotate at a constant angular velocity unless a net torque is acting on it. Since the meter scale is not accelerating or decelerating, but moving at a uniform velocity, it implies that there is no net torque acting on it. Hence, the net torque acting about the centre of mass of the scale is also zero.
Similar Questions
A micrometer screw has a pitch of 0.5 mm. the circular scale is divided into 50 parts. The least ofmicrometer is
The pitch and the number of divisions, on the circular scale for a given screw gauge are 0.5 mm and 100 respectively. When the screw gauge is fully tightened without any object, the zero of its circular scale lies 3 division below the mean line. The readings of the main scale and the circular scale, for a thin sheet, are 4.5 mm and 48 respectively, the thickness of the sheet is:
Among the primary scales of measurement, the _________ has an absolute zeroa.nominal scaleb.interval scalec.ratio scaled.ordinal scalee.random scale
A uniform metre scale of length 1m is balanced on a fixed semi–circular cylinder of radius 30 cm as shown in figure. One end of the scale is slightly depressed and released. The time period (in seconds) of the resulting simple harmonic motion is
Among the primary scales of measurement, the _________ has an absolute zeroa.interval scaleb.random scalec.ratio scaled.ordinal scalee.nominal scale
Upgrade your grade with Knowee
Get personalized homework help. Review tough concepts in more detail, or go deeper into your topic by exploring other relevant questions.