CBSE 11TH PHYSICS - Online Test
Q1. The scalar product of two vectors A and B in terms of the projections of the vectors on the x, y and z axis is
Answer : Option C
Explaination / Solution:
A = Ax i+ Ay j+ Azk
B = Bx i+ By j+ Bzk
A. B = (Ax i+ Ay j+ Azk). ( Bx i+ By j+ Bzk)
A. B = AxBx + AyBy + AzBz
Q2. Magnitude of displacement of a particle is
Answer : Option C
Explaination / Solution:
The maximum possible value for displacement is the distance travelled, so it cannot be of a greater value than distance (path length).
The magnitude of the displacement is always less than or equal to the distance traveled. If two displacements in the same direction are added, then the magnitude of their sum will be equal to the distance traveled.
Q3. Thermodynamic state of a system is an equilibrium state
Answer : Option D
Explaination / Solution:
In thermodynamic equilibrium there are no net macroscopic flows of matter or of energy, either within a system or between systems.
Q4. The importance of the elastic behavior of materials is
Answer : Option D
Explaination / Solution:
More the elastic a material is , more it has the property to regain its original position which is required in construction works.
Q5. Inertia refers to
Answer : Option B
Explaination / Solution:
Inertia is the resistance of any physical object to any change in its state of motion; this includes changes to its speed, direction, or state of rest. It is the tendency of objects to keep moving in a straight line at constant velocity. Inertia is a property of matter by which it continues in its existing state of rest or uniform motion in a straight line, unless that state is changed by an external force.
Q6. Pressure p at any point in a fluid at rest is
Answer : Option D
Explaination / Solution:
It is important to note that it is valid only for a fluid at rest. In the case of a moving fluid, pressures in different directions could be different depending upon fluid accelerations in different directions.
Q7. According to Atomic Hypothesis:
Answer : Option C
Explaination / Solution:
atomic hypothesis that all things are made of atoms—little particles that move around in perpetual motion, attracting each other when they are a little distance apart, but repelling upon being squeezed into one another.
Q8. 180 equal intervals between two reference points on Fahrenheit scale correspond to
Answer : Option B
Explaination / Solution:
ΔTC100=ΔTF180
Q9. Unit for a fundamental physical quantity is
Answer : Option C
Explaination / Solution:
Unit is the reference used as the standard measurement of a physical quantity. The unit in which the fundamental quantities are measured are called fundamental unit and the units used to measure derived quantities are called derived units.
Q10. Period of a periodic motion is the ________ interval of time after which the motion is __________.
Answer : Option B
Explaination / Solution:
Time period of an oscillatory motion is the smallest interval of time for one complete oscillation.As when we apply the force on the bob,bob moves from mean position to extreme position then form extreme position to mean position and then again from mean to extreme in opposite direction and at last come to mean position.The time taken by bob in this whole process is called period of oscillation.
