Question

A motor car having a mass 50 kg moving with a velocity of 40 metre per second and it takes 2 seconds to stop after the brakes are applied the force exerted by the brakes on the motor car will be *
- 100N
100N
1000N
- 1000N
Which of the following is not an application of Newton's second law of motion *
Cricket player moves his hand backward on catching a fast cricket ball
Walking of a person in the ground
A high jumping athlete is provided either a cushion or a heap of sand on the ground to fall upon
All the above
Which of the following statement is correct *
The slope of velocity time graph represents acceleration
In velocity time graph area under curve represents the distance
The final velocity of an object cannot be calculated by using only second equation of motion
All the above
A motorboat starting from rest on a on a lake accelerated in a straight line at a constant rate of 3 metre per second square for 2 minutes the distance travelled by the boat during the time will be *
8 m
4 m
28.8 m
14.4 m
Choose the incorrect pair *
Elements - basic form of matter that cannot be broken down into simpler substances by chemical reaction
Iodine - non metal
Non metals -conduct heat and electricity
Metals - Sonorus
Choose the incorrect pair *
Force - Newton
Momentum - kg m/second
Force - kg m/second
Velocity - meter/second
Which of the following shows 'Tyndall effect' *
Copper sulphate solution
Mist
camphor
Soda water
Fractional distillation process is used for *
Separation of different gases from air
Separation of mixture of two or more miscible liquids for which the difference in boiling point is less than 25 k
Different fractions from petroleum products
All all the above
Which one of the following is incorrect *
Colloidal solution -tyndall effect
Sublimation -Naphthalene
Milk -Sol
Chromatography -separation of dyes
Which of the following statement is incorrect about solution *
A solution of iodine in alcohol known as tincture of iodine has iodine solid as the solute and alcohol liquid as a solvent
The particles of solution are small
The solute particles can be separated from the mixture by the process of filtration
They do not scatter a beam of light passing through the solution

This is a required question
Acceleration is *
Rate of change of speed
Change of speed
Rate of change of velocity
Change of velocity
Which one of the following statement is incorrect *
the rate of change of momentum of an object is proportional to the applied balanced force in the opposite direction of force
Inertia is directly proportional to the mass of an object
Momentum has both magnitude and direction
Force of friction always opposes the motion of the object
Which one of the following statement is incorrect *
The magnitude of displacement may be greater than the magnitude of distance
The magnitude of displacement may be zero
The rate of change of velocity is called acceleration
Displacement time graph presents velocity
A stone is thrown in vertically upward direction with a velocity of 12 metre per second if the acceleration of the stone during its motion is 10 metre per second square in the downward direction then the height attained by the stone and time taken by the object to reach the ground will be respectively *
7.2 m and 1.2sec
14.4 m and 1.2 sec
7.2 m and 2.4sec
14.4 m and 2.4 sec
Which of the following physical quantity can not be negative *
Distance
displacement
Acceleration
Velocity
Which of the following metal is present in liquid state at room temperature *
Sodium
Mercury
Lead
All of the above
Scalar quantity has
both magnitude and direction
Has magnitude only
Has direction only
None of these
Which of the following is correct mathematical *
F = m x a
F x t = m ( v - u)
mat+ mu =mv
All the above
Which of the following is a physical change *
Change of ice in water
Rusting of iron
Glowing of bulb
Burning of candle​

Answer 1

Force=mass*acceleration

f=m×tv−u

f=1000×40−108×185

=1000×(−7.5)

∴f=−7500N

opposing force is denoted by negative sign.

Answer 2

Answer:

A motor car having a mass 50 kg moving with a velocity of 40 metre per second and it takes 2 seconds to stop after the brakes are applied the force exerted by the brakes on the motor car will be *

- 100N

100N

1000N

- 1000N

Which of the following is not an application of Newton's second law of motion *

Cricket player moves his hand backward on catching a fast cricket ball

Walking of a person in the ground

A high jumping athlete is provided either a cushion or a heap of sand on the ground to fall upon

All the above

Which of the following statement is correct *

The slope of velocity time graph represents acceleration

In velocity time graph area under curve represents the