Advertisements
Advertisements
प्रश्न
Define force.
Advertisements
उत्तर
Force is a physical cause that changes or may tend to change the state of rest or the state of motion of an object.
APPEARS IN
संबंधित प्रश्न
What is the SI unit of the moment of force?
Where can a body execute free vibrations?
A half metre rod is pivoted at the centre with two weights of 20gf and 12gf suspended at a perpendicular distance of 6 cm and 10 cm from the pivot respectively as shown below.
1) Which of the two forces acting on the rigid rod causes clockwise moment?
2) Is the rod in equilibrium?
3) The direction of 20 kgf force is reversed. What is the magnitude of the resultant moment of the forces on the rod?
A force always produces both the linear and turning motions.
Write the expression for the moment of force about a given axis of rotation.
A wheel of diameter 2 m can be rotated about an axis passing through its center by a moment of force equal to 2.0 Nm. What minimum force must be applied on its rim?
Name and define the S.I. and C.G.S. units of force. How are they related?
What do you understand by the clockwise and anticlockwise moment of force? When is it taken positive?
A wheel of diameter 2 m is shown in the figure with the axle at O. A force F = 2 N is applied at B in the direction shown in the figure. Calculate the moment of force about
- the centre O, and
- the point A.
A uniform metre rule of weight 10gf is pivoted at its 0 mark.
What moment of force depresses the rule?
Classify the following amongst contact and non-contact forces.
Frictional force
One joule is the amount of work done when a force of ......... moves a body through a distance of .......
Three forces A, B and C are acting on a rigid body which can turn about O in fig.9. If all the three forces are applied simultaneously, in which direction will the body move? Explain.
Calculate the length of arm of couple, if a force of 13 N produces a moment of couple of 14.3 Nm.
A door lock is opened by turning the lever (handle) of length 0.2 m. If the moment of force produced is 1 Nm, then the minimum force required is ______.
A metal rod AB of length 80 cm is balanced at 45 cm from the end A with 100 gf weights suspended from the two ends.
- If this rod is cut at the center, C, then compare the weight of AC to the weight of BC. (Use >, < or =)
- Give a reason for your answer in (a).
A person standing in front of a cliff fires a gun and hears its echo after 3 s. If the speed of sound in air is 336 ms−1.
- Calculate the distance of the person from the cliff.
- After moving a certain distance from the cliff, he fires the gun again, and this time the echo is heard 1.5 s later than the first. Calculate the distance that the person moved.
