1.
A test charge is a
A. charged object with a very small mass.
B. charged object with a very small charge.
C. point charge which has no effect on the electric field in which it is placed.
D. point charge which slightly changes the electric field in which it is placed.
(Total 1 mark)
2. This question is about gravitational and electric fields.
(a) The equation for the magnitude of the gravitational field strength due to a point mass may
be written as below.
KX
2
Y= s
The equation for the magnitude of the electric field strength can also be written in the
same form.
In the table identify the symbols used in the equation.
Symbol Gravitational field quantity Electrical field quantity
Y
K
X
s
(4)
IB Questionbank Physics 1
(b) The magnitude of the electrostatic force between the proton and electron in a hydrogen
atom is FE. The magnitude of the gravitational force between them is FG.
FE
Determine the ratio FG .
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(3)
(Total 7 marks)
3. In Newton’s universal law of gravitation the masses are assumed to be
A. extended masses.
B. masses of planets.
C. point masses.
D. spherical masses.
(Total 1 mark)
4. The electric field strength at a point may be defined as
A. the force exerted on unit positive charge placed at that point.
B. the force per unit positive charge on a small test charge placed at that point.
C. the work done on unit positive charge to move the charge to that point from infinity.
D. the work done per unit positive charge to move a small test charge to that point from
infinity.
(Total 1 mark)
IB Questionbank Physics 2
5. An electron is moving in air at right angles to a uniform magnetic field. The diagram below
shows the path of the electron. The electron is slowing down.
Which of the following correctly gives the direction of motion of the electron and the direction
of the magnetic field?
Direction of motion Direction of magnetic field
A. clockwise into plane of paper
B. clockwise out of plane of paper
C. anti-clockwise into plane of paper
D. anti-clockwise out of plane of paper
(Total 1 mark)
6. This question is about gravitational fields.
(a) Define gravitational field strength.
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(2)
IB Questionbank Physics 3
–1
(b) The gravitational field strength at the surface of Jupiter is 25 N kg and the radius of
7
Jupiter is 7.1 10 m.
(i) Derive an expression for the gravitational field strength at the surface of a planet in
terms of its mass M, its radius R and the gravitational constant G.
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(2)
(ii) Use your expression in (b)(i) above to estimate the mass of Jupiter.
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(2)
(Total 6 marks)
7. This question is about gravitational fields.
(a) Define gravitational field strength.
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(2)
IB Questionbank Physics 4
–1
(b) The gravitational field strength at the surface of Jupiter is 25 N kg and the radius of
7
Jupiter is 7.1 10 m.
(i) Derive an expression for the gravitational field strength at the surface of a planet in
terms of its mass M, its radius R and the gravitational constant G.
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(2)
(ii) Use your expression in (b)(i) above to estimate the mass of Jupiter.
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(2)
(Total 6 marks)
IB Questionbank Physics 5
