A 5 kg object starting at rest, falls to the ground from a height of 10 m. Just before hitting the earth, what will be the K.E.? if the friction force offered by the air is 1 N.? 480 J 490 J 500 J None of these
The biggest unit of energy is _ whereas the smallest unit of energy is _ (out of the following)? Kilowatt hour, Erg Kilowatt hour, eV Kilowatt hour, Gram calorie watt hour, Erg
The K.E. is 1200 J for a mass 690 kg having momentum _.? 1286 kgm^2 12086 kgm^2 2001 kgm^2 None of these
The angle between centripetal force and centrifugal force, for a body moving in a circle is? 90 180 45 degree None of these
A well known fact is that work done by the centripetal force is zero since speed remains constant during circular motion, what about K.E. during the same circular motion?? Of course it is zero as well. It remains constant It does not remains constant. None of these
A body of mass 50 kg is standing in a lift. What happens to mass of the body when the lift is going up and is about to stop at 3rd floor?? Increases Decreases Remains same None of these
If the lift moves upward with a deceleration, having a person standing still in the lift, what will happen to the Real weight of the person?? Increases Decreases Remains same None of these
The ratio of displacement along diameter of circle and total distance along a semi-circle is:? 1: π π : 1 1 : 1 None of these
Bernoulli’s equation was derived in today’s known form, by? Daniel Bernoulli first wife of Daniel Bernoulli second wife of Daniel Bernoulli L. Euler
[PPSC 2022] The terms (other than pressure) in Bernoulli equation have the dimension of:? Pressure Gradient Velocity Gradient Modulus of Elasticity None of these
Temperature of a gas increases from 10C to 20C, what happens to the viscosity of the gas? Increases Decreases Remains same None of these
Terminal velocity does not depends upon? Falling time Area mass viscosity
[PPSC 2020, 2022) Bernoulli equation is an expression of:? Law of conservation of mass Law of conservation of Energy
Moment of inertia of __ will be used while studying Earth’s Orbital Angular momentum?? Sphere Disc Hoop None of these
A sphere, disk and hoop with same mass and same radius is left on an inclined plane, which of the three will reach the ground first?? Sphere Disc Hoop None of these
The time period of simple pendulum is 1 sec when displacing at an angle of 1 degree. If the angle is doubled, the period becomes:? 1 sec 2 sec 0.5 sec None of these
A tunnel has been dug through the center of the earth and a ball is released in it. the ball will? go through the tunnel and reach the other end Will stop at the center of the earth perform simple harmonic motion None of these
For a watch, the time period of the second’s hand is:? 1 sec 1 minute 1 hour None of these
The force of gravity above the earth’s surface is proportional to _ and inside the earth it is proportional to __? 1/r^2, r 1/r, r r, 1/r^2 r, 1/r None of these
Which of the following waves cannot be polarized?? Radio Waves Micro Waves Ultrasound X Rays