Page 82 - CITS - WCS - Mechanical
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WORKSHOP SCIENCE - CITS
3 A bus with full =0.25\times50=12.5~kg 4500 kg is running on the road. If the coefficient of friction between the
types and the road is 0.30, then calculate the force of friction.
Solution:
Normal reaction A=4500~kg
Coefficient of friction µ =0.30
Force of Friction = µ .R
=0.30 x 4500
=1350~kg
4 A glass block of 400 grams has been placed on the table. The glass is connected by a string to a 40 grams
scale pan. The string passes over a pulley. When a weight of 60 grams is placed on the scale pan, the block
starts sliding. Find out the co-efficient of Induction between wood and glass
Solution:
Scale pan means a small container Weight of 60 grams placed on the scale pan. Weight of scale pan is given as
40 grams. Force required to move the glass block =60 grams + 40 grams =100 grams
F =Force required to start siding =100 grams
R=Normal Reaction weight of glass block = 400 grams
Let µ co-efficient of friction
We know:
F= µ .R
µ= F/R=100/400=0.25
Co-efficient of friction=0.25 Ans.
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CITS : WCS - Mechanical - Exercise 6 CITS : WCS - Mechanical - Exercise 6
