Q3: If we increase the length of a
spanner 4 times what would be the
effect on applied force if torque
produced by the spanner remains
constant?
Answers
Answer:
Selina solutions
Grade 8
Biology
Mathematics
Physics
Chapters in CONCISE Physics - Middle School - 8
Exercises in Force and Pressure
Question 13
Q13) Explain the following:
(i) The spanner (or wrench) has a long handle.
(ii) The steering wheel of a vehicle is of large diameter.
(iii) The hand flour grinder is provided with a handle near the rim.
(iv) It is easier to open the door by pushing it at its free end.
(v) A potter turns his wheel by applying a force through the stick near the rim of the wheel.
Solution
Transcript
Solution:
(i) Spanner has a long handle to produce larger turning moments when a small force is applied at the handle end.
(ii) The steering wheel is of large diameter to decrease the amount of force required to produce the turning effect.
(iii) The stone of hand flour grinder is provided with a handle near the rim, i.e. at maximum distance from centre so that it can be easily rotated about the iron pivot at its centre by applying small force at the handle.
(iv) It is easier to open the door by applying force at its free end because the increased perpendicular distance decreases the amount of force required to open the door as the moment of force is the product of force and the perpendicular distance.
(v) A potter’s wheel has a wheel pivoted at the centre. The potter turns the wheel by means of a stick at the rim of the wheel which increases the perpendicular distance.
Explanation:
torque = applied force. x perpendicular distance
= F¹ x R¹ ------i
torque = effect on force x 4 R¹
F¹ x R¹ = effect on force x 4 R¹
effect on force = 1/4 times of applied force.