CBSE 11TH PHYSICS - Online Test

Answer : Option A
Explaination / Solution:

if a body of mass m move with velocity u under the action of force F. Its velocity become v after displaced by s. then v2=u2+2as v2−u2=2as mv2−mu2=2mas 12mv2−12mu2=Fs Kf−Ki=W ΔK=W

v2=u2+2asv2−u2=2asmv2−mu2=2mas12mv2−12mu2=FsKf−Ki=WΔK=W

Answer : Option D
Explaination / Solution:

When a vector is multiplied by a positive number (for example 2, 3 ,5, 60 unit etc.) or a scalar only its magnitude is changed but its direction remains the same as that of the original vector.

Answer : Option B
Explaination / Solution:
No Explaination.

Answer : Option C
Explaination / Solution:

A wall which prevents thermal interaction is known as adiabatic wall and a system enclosed within an adiabatic wall is called thermally isolated. If exchange of heat takes place between the system and surroundings through the boundary wall, the boundary is called diathermic wall.

Answer : Option B
Explaination / Solution:

If mass does not change then acceleration of a particle is dependent on the forces acting upon the particle and the particle's mass. For a given particle, if the net force is increased, the acceleration is increased. For a given net force, the more mass a particle has, the less acceleration it has.

F=ma=mdvdt=d(mv)dt=dpdt.${\displaystyle \mathbf{F}=m\mathbf{a}=m\frac{\mathrm{d}\mathbf{v}}{\mathrm{d}t}=\frac{\mathrm{d}(m\mathbf{v})}{\mathrm{d}t}=\frac{\mathrm{d}\mathbf{p}}{\mathrm{d}t}}.$

hence the rate of change of momentum of a body is directly proportional to the applied force

 

Answer : Option D
Explaination / Solution:

According to Pascal's Law,

Change in Pressure (P-P0) = hρg

if h=0 then P-P0 = 0

and P=P0

Answer : Option C
Explaination / Solution:

Atoms in a gas are well separated with no regular arrangement. Atoms vibrate and move freely at high speeds Atoms in a liquid are close together with no regular arrangement. Atoms vibrate, move about, and slide past each other. Atoms in a solid are tightly packed, usually in a regular pattern. Atoms vibrate (jiggle) but generally do not move from place to place.

Answer : Option A
Explaination / Solution:

V∝NTPPVNT=kN=μNAPVμT=NAk=RPV=μRT

Answer : Option B
Explaination / Solution:

Derived units are units which may be expressed in terms of base units by means of mathematical symbols of multiplication and division.

For example, the SI derived unit of area is the square metre (m​​​​​​2), and the SI derived unit of density is the kilogram per cubic metre (kg/m3 or kg m​​​​​​-3).

The names of SI units are written in lowercase.

Answer : Option A
Explaination / Solution:
No Explaination.