for both electric and gravitational fields.
for electric but not gravitational fields.
for gravitational but not electric fields.
I. mass of Earth
II. radius of Earth
III. mass of the rocket.
Which of the above factors is/are correct?
I and II only
I and III only
What is the unit of Gε0, where G is the gravitational constant and ε0 is the permittivity of free space?
E = 0
`E = (mg)/q`
`E > (mg)/q`
What is the weight of the satellite and the gravitational potential energy of the satellite when placed in orbit ?
Point P is the midpoint between the objects and is a distance R from the surface of each object. What is the gravitational potential at point P?
The two objects could be
electric charges of the same sign only.
electric charges of opposite sign only.
masses or electric charges of any sign.
A point mass m is placed on the middle line and is then released. Values given in MJ kg–1.
Which is correct about the direction of motion and the acceleration of the point mass?
Which of the following gives the direction of the electric field due to the charges at X, Y and Z?
The sketch graph shows how the gravitational potential V of a planet varies with distance r from the centre of the planet of radius R0.
The magnitude of the gravitational field strength at the point r = R equals the
area between the graph and the r-axis between r = R and r = R0.
gradient of the graph at r = R.
inverse of the gradient of the graph at r = R.
value of V at r = R divided by R2.
The three quantities that depend on the distance r of the spacecraft from the centre of the Earth are the
I. gravitational potential energy of the spacecraft
II gravitational field strength acting on the spacecraft
III. gravitational force acting on the spacecraft.
Which of the quantities are proportional to `1/r^2`?
I and II only
I and III only
II and III only
I, II and III
An electron of mass me orbits an alpha particle of mass mα in a circular orbit of radius r. Which expression gives the speed of the electron?
The electric potential is zero
at the origin of the axes only.
along both the x-axis and the y-axis.
along the y-axis only.
along the x-axis only.
What is the distance from the centre of the planet at which the total gravitational potential has a maximum value?
2R and 20R
The mass of the Earth is ME and the mass of the Moon is MM. Their respective radii are RE and RM.
The diagram below shows a particle with positive charge q accelerating between two conducting plates at potentials V1 and V2.
Which of the following is the kinetic energy gained by the charge in moving between the plates?
What is the path followed by the particle?
Scattering of alpha particles
The work done by an external force in moving a test charge +q from d = 2r to d = r is equal to q multiplied by the
shaded area under graph 1.
shaded area under graph 2.
average value of the electric field.
average value of the electric potential.
per unit mass in moving a small mass from infinity to the point.
in moving a unit mass from infinity to the point.
in moving a small mass from infinity to the point.
per unit mass in moving a unit mass from infinity to the point.
Plate X is at Earth potential (0 V) and the potential of plate Y is V0.
Which of the following is correct in respect of the magnitude and the direction of the electric field between the plates?
both the radius and the mass of the planet.
only the radius of the planet.
only the mass of the planet.
only the gravitational field strength at the surface of the planet.