A ball placed on a table starts rolling when table is tilted. Which is the force which causes this motion?
Friction
Push by table
Rolling force
Gravitational pull by earth
Calculate the gravitational force of earth acting on a body of mass 1 kg ?
8.9 N
9.8 N
980 N
1 N
One arm of a glass U-tube is open to the atmosphere, whereas the other vertical arm is connected to a gas supply. The difference in levels of mercury (density = 13.6 g cm-3) between the vertical arms of the U-tube manometer is h = 3 cm. If the atmospheric pressure is 760 mm Hg and the gravitational acceleration is 9.8 m s-2, Calculate the pressure of the gas ?
1.053 × 106dynes cm-2
1.074 × 104dynes cm-2
3.998 × 104dynes cm-2
1.017 × 107dynes cm-2
S.I. unit of force is
Kg ms-1
Kg ms
Nm
N
It is better to use a sharp tripped nail than a blunt nail because
The tip with the smallest area will produce a higher pressure when a small force is applied
A sharp tipped nail needs a larger force to drive it into the wooden surface
The sharp tip saves cost as less raw materials are required to make such nails
The sharp tip has a spiralling effect when the nail is hit on the head
The pressure exerted by a body is 8650 Pa when it is placed on a wooden plank.If the area of contact is 2500cm2,find the weight of the body ?
2162.5 N
2612.5 N
3125 N
3256 N
Which of the following actions involves both pulling and pushing forces?
Squeezing toothpaste out of a tube
Wringing a wet towel
Closing a door
Typing a letter
What is the atmosphere compared with?
an ocean of water
a tightly packed envelope of air molecules
a tightly packed envelope of air
a balnket of air surrounding the Earth
Pressure varies with force (F) as (providing area is same)
F
F2
Sohan is unable to lift a box off the ground. The force that make it difficult to do so is
i) The weight of the box
ii) The weight of the sohan
iii) Gravity
iv) Friction
i and ii only
i and iii only
ii and iii only
iii and iv only
