Efficiency of pulley
1.70%
2.76%
3.80%
4.86%
Emergent ray is
1.AB
2.BC
3.CD
4.None of these
Kinetic energy at height 10 m
1.500J
2.1000J
3.2000J
4.3000J
Potential energy at maximum height
1.1000J
2.2000J
3.3000J
4.4000J
A ball of mass 20 kg is thrown in upward direction. It reach, til the height 20 m from the ground and comes back to the earth, if the value of g 10 m/sec, answer the following question. Kinetic energy when at the maximum height
1.mgh
2.1/2mv2
3.0
4.none
Angle of deviation does not depend on
1.θ
2.P
3.u
4. φ
Angle of deviation will be :
1.α
2.β
3.r
4. θ
Angle of prism will be
1.θ
2.α
3.r
4.none ese
Choose incorrect statement
1.Sound wave require medium to propagate
2.Range of audibility is 20 Hz to 20,000 Hz
3.the sound of frequency greater than audibility range is called ultrasonic
4.Infrasonic waves are audible for human cars
Choose incorrect statement about concave lens
1.The image is always virtual
2.The image is always real
3.The image is always diminished
4.The image is always erect
Choose the correct formula for magnifying power of lens
1. m=1+D/F
2. m=D/F
3. m=1+F/D
4.m=D/F+2
Choose the correct statement
1.EM waves requires a material medium for propagation
2.EM waves are transverse wave
3.EM waves reflects by Electric & Magnetic field
4.The velocity of EM waves not changes when medium change
Choose the correct statement with respect to lateral displacement
1.It occurs in case of a rectangular glass slab
2. It occurs when ray passes through two optical media
3. It is directly proportional to thickness of glass slab
4. Both 1 and 3
Choose the incorrect statement
1.Dispersion of white light occurs at the first surface of prism
2.Deviation of light occurs at both the surface of prism
3. The prism produce colours
4.The prism splits the various colours present in the light incident on it
Choose the incorrect statement
1.An echo is heard only if the distance of person producing sound is long enough to allow the reflected sound to reach a person at least 0.1 sec after original sound is heard
2.time taken to hear echo is 2d/v
3.To hear the echo distinctly the reflecting surface in air should be at minimum 17m distance.
4.The size of reflector should be small enough as compared to wavelength of the sound
Energy gained by load in a height of 10 m in 10 sec:
1.5000J
2.6000J
3.7000J
4.8000J
If frequency of a yellow light is 6 x 10Hz. Then Wavelength of light in m
1.6x 101m
2.2x 10m
3.0.5x10 m
4.0.5m
If the object is at F, the size of image will be
1.highly magnified
2.highly diminished
3.magnified
4.diminished
If the position of object is at F1, the position of image will be
1.Beyond 2F2
2.at 2F2
3.at infinity
4.on the same side, behind the object
If the position of object is beyond 2F, the position of image will be:
1.at F2
2.between F2 & 2F2
3.at 2F2
4.beyond 2F2
If the work done by a heart is 2J per beat. The power of the heart if it beat 70 times in 1 minute (approx.)
1.2J/sec
2.4 J/sec
3.5J/sec
4.6J/sec
In block and tackle system the mechanical advantage is:
1.number of pulley
2.One less than number of pulley
3.2 (Total number of pulley)
4.load/effort
In linear motion the acceleration is
1.Positive
2.Negative
3.Zero
4.Constant
Potential energy of ground
1.4000 J
2.400J
3.0
4.none
Power developed by boy in raising load:
1.600W
2.700W
3.800W
4.900W
The force which is not a real force
1.Force of tension
2.Centripetal force
3.Centrifugal force
4.Gravitational force
The image formed will be on the same side, behind the object if the object is at:
1.At Infinity
2.Between lens and F1
3.Between F1, &2F1
4.at 2F1
The relationship to evaluate the efficiency is
1.power input/power output
2.power input x power output
3.power output/power input
4.power output x power input
Total energy of pendulum:
1.0.1J
2.0.01 J
3.0.001J
4.1J
Velocity of bob at mean position
1.2m/sec
2.1 m/sec
3.1414 m/sec
4.none of these
Velocity ratio of the pulley
1.0
2.1
3.2
4.3
Wavelength range of yellow light is
1.4000A-4460A
2.4640A-5000A
3.5780A-592mA
4.5780A-592mA
Work done by effort is
1.Effort x load
2.load x distance moved by effort
3.effort x distance moved by effort
4.none of these