Gravitation
If the zero of potential energy is at infinity the total energy of an orbiting satellite is negative of its ______ energy
Kinetic Energy
A force at an angle of 120o to the direction of motion. Is the work done positive, negative, or zero
Negative
if the length of a conductor wire is doubled its conductance will be
1/4 of the original value
the direction of the electric field at a point is the direction of force on this type of test charge
Positive Test Charge
A bar magnet is dropped along the axis of a coper ring held horizontally. The acceleration of fall is
Less than g
What happens to the orbital velocity of a satellite if orbital radius is doubled
Decreases
A person climbs up a rope at a constant speed. What fraction of his energy output is converted into potential energy gain?
Less than one
In a closed circuit the current I (in ampere) at an instance of time t (in seconds) is given by I=4-0.08t the number of electrons flowing in 50 seconds through the cross section of the conductor is
6.25 x 1020
Two charges of 2μC and -3μC are separated by a distance of 0.5m In air find the magnitude of the force between them.
0.216N
The phenomenon that limits the rise of current in a RL circuit when the circuit is first closed
Self-Inductance
What is the angle between the equatorial plane and orbital plane of Geostationary satellite
A trolley of mass 300kg carrying a sand bag of 25kg is moving uniformly with the speed of 27km/h on a frictionless track after a while the sand starts leaking out of a hole o the floor or the trolley at the rate of 0.05kg/sec what is the speed of the trolley after the entire sandbag is empty?
27km/h
If the electric current in a lamp decreases by 5% then the power output decreases by
10%
2 Charged spherical conductors of radius R1 and R2 are connected by a wire then the ratio of the surface charge densities of the spheres is
In an AC generator, if the number of turns of the coil is doubled while keeping angular velocity and magnetic flux density constant, by what factor does the peak induced emf change?
2
The period of revolution of a planet A around the sun is 8 times that of B. How many times is the distance of A from the sun greater than that of B from the sun.
4
Calculate the power of a crane in watts, which lifts a mass of 100kg to a height of 10m in 20s.
490W
A storage battery of emf 8.0v and internal resistance of 0.5 ohm is being charged by a 120v DC supply using a series resistor of 15.5 ohm what is the terminal voltage of the battery during charging
11.5V
Two copper balls each weighing 10 grams are kept in air 10cm apart if one electron from every 106 atoms is transferred from one ball to the other the coulomb force between them is ( atomic weight of copper 63.5g)
2.0x108N
An average induced e.m.f of 1V appears in a coil when the current in it is change from 10A in one direction to 10A in opposite direction in 0.5sec. Self-Inductance of the coil is?
25mH
The earth (6x1024 kg) revolves around the sun with an angular velocity of 2x10-7 rad s-1 in a circular orbit of radius 1.5x108km. The force exerted by the sun on the earth (in newton’s) is?
36x1021
Suppose the average mass of rain drops is 3.0x10-5 kg and their average terminal velocity 9m s-1. Calculate the energy transferred by rain to each square meter of the surface at a place which receives 100cmof rain in a year
4.05 x 104
The resistance of a platinum wire at 0oC is 2Ω and 6.8Ω at 80oC. The temperature coefficient of resistance of the wire is?
3x10-2C-1
Two electric dipoles of moment p and 27p are placed in opposite directions on a line at a distance of 10cm the electric field will be 0 at point between the dipoles of moment p is?
2.5cm
A long solenoid has 1000 turns. When a current of 4wA flows through it, the magnetic flux linked with each turn of the solenoid is 4x10-3 Wb. The self-inductance of the solenoid is
1