Mechanics

151.Skating on ice shows that on increasing the pressure the melting point of ice is
 
A. Increases
 
B. Happens to
 
C. Remains unchanged
 
D. First decreases then increases
 
Option”B” is correct
152.The ball keeps on dancing in the splash of water at the intersections because-
 
A. The pressure decreases as the velocity of water increases
 
B. Higher the velocity of the water the higher the pressure
 
C. Due to the surface tension of water
 
D. Due to viscosity of water
 
Option”A” is correct
153.A heavy iceberg melts from the bottom rather than the top because-
 
A. Low temperature is high
 
B. Melting point decreases due to high bottom pressure
 
C. Ice is not a real solid
 
D. None of the above
 
Option”B” is correct
154.A person trapped in a swamp is advised to lie down because-
 
A. Pressure decreases as the area increases
 
B. Greater the area the greater the pressure
 
C. There is no relation between pressure and area
 
D. For all of the above reasons
 
Option”A” is correct
155.When two pieces of ice are pressed together, the pieces stick together because-
 
A. Melting point of ice decreases due to high pressure
 
B. Melting point of ice increases due to high pressure
 
C. Melting point of ice first decreases with increase in pressure and then increases
 
D. There is no relation between pressure and melting point
 
Option”A” is correct
156.Often, light thatched or tin roofs get blown away during strong storms because-
 
A. Roofs are complex
 
B. Roofs are not taxed
 
C. The high velocity air flowing over the roof creates pressure on the roof surface and the pressure remains normal under the roof.
 
D. Thatched roofs blow away automatically in strong wind
 
Option”C” is correct
157.Wide strips of wood or concrete are placed under the rail track so that-
 
A. It can absorb shocks
 
B. How to apply fish straps correctly
 
C. Tracks stay parallel
 
D. Reduce the pressure exerted by the train
 
Option”D” is correct
158.Sometimes blood comes out from the nose and mouth of people on the mountains, because
 
A. Blood pressure increases with altitude
 
B. Blood pressure decreases with increase in altitude
 
C. Atmospheric pressure increases with increase in altitude
 
D. Atmospheric pressure decreases with increase in altitude
 
Option”D” is correct
159.Ink comes out from fountain pen in airplane because-
 
A. Air pressure decreases with increase in altitude
 
B. Air pressure increases with altitude
 
C. Air pressure remains unchanged with increase in altitude
 
D. None of the above
 
Option”A” is correct
160.If the mass of the earth remains W and the radius decreases by 1%, then the value of g on the Earth’s scale-
 
A. 0.5%’ will increase
 
B. 2%’ will increase
 
C. 0.5%’ will decrease
 
D. 2%’ will decrease
 
Option”B” is correct