# Physics Past Questions

Exam Body:

### Question 1

Two magnets are used to magnetize a soft iron bar PQ as illustrated in the diagram given. The correct polarity at P and Q respectively

A) S and N

B) N and S

C) S and S

D) N and S

Exam Body: WAEC

### Question 2

In storing magnets, keepers are used to

### Options

A) reduced self-demagnetization

B) cancel the effect of the earth's magnetic field

C) protect the magnet from stray electric field

D) increase the strangth of the magnets

Exam Body: WAEC

### Question 3

A $$10\mu \mathrm{C}$$ charge moves with a velocity of $$1.0 \times 10^5 ms^{-1}$$ at right angle to a uniform magnetic field of flux density $$5.0 \times 10^{-4}T.$$ Calculate the force on the charge.

### Options

A) $$5.0 \times 10^{-5} \mathrm{N}$$

B) $$5.0 \times 10^{-4} \mathrm{N}$$

C) $$5.0 \times 10^5 \mathrm{N}$$

D) $$5.0 \times 10^6 \mathrm{N}$$

Exam Body: WAEC

### Question 4

Which of the following statements is not correct about steel and soft iron?

### Options

A) steel is more magnetized than soft iron

B) permanent magnets are usually made of steel

C) soft iron is more readily magnetized than steel

D) soft iron more readily loses its magnetism than steel

Exam Body: WAEC

### Question 5

What determines the polarity at the ends of an electromagnet? The

### Options

A) magnitude of the current passing through the wire

B) material of the core of the magnet

C) material of the coil

D) direction of current in the wire

Exam Body: WAEC

### Question 6

How many beta particle(s) are emitted in the radioactive decay of $$^{198}_{79} \mathrm{Au} \leftarrow ^{198}_{80} \mathrm{Hg}$$?

A) 1

B) 2

C) 3

D) 5

Exam Body: WAEC

### Question 7

The phenomenon by which two light atomic nuclear combine to form a heavy nuclide with the release of energy is known as

### Options

B) nuclear fusion

C) nuclear fission

D) chain reaction

Exam Body: WAEC

### Question 8

In a p-type semiconductor, the

### Options

A) number of holes are equal to the number of electrons

B) electrical resistivity increases

C) electrons are the majority charge carriers

D) holes are the majority charge carriers

Exam Body: WAEC

### Question 9

Let Δx be the uncertainty in the measurements of position and Δp the uncertainty in measurement of momentum. The uncertainty principle relation is given as

A) Δx . Δp = h

B) Δx . Δp ≤ h

C) Δx . Δp ≥h

D) Δx . Δp > h

Exam Body: WAEC

### Question 10

Two objects of masses 80kg and 50kg are separated by a distance of 0.2m. If the gravitational constant is 6.6 x 10-11Nm kg, calculate the gravitational attraction between them.

A) 4.9 × 10-9N

B) 1.3 × 10-6N

C) 6.6 × 10-8N

D) 6.6 × 10-6N

E) 2.6 × 10-9N

Exam Body: WAEC

### Question 11

1kg of boiling water at 100°C is poured into an aluminium hot water bottle at 16°C. The temperature of the water quickly falls to 96°C. Assuming that there is no loss of heat, the mass of the bottle is

A) 0.25kg

B) 0.5kg

C) 0.05kg

D) 0.75kg.

Exam Body: JAMB

### Question 12

The resultant of two forces is 50N. If the forces are perpendicular to each other and one of them makes an angle of 30° with the resultant, find its magnitude

A) 57.7N

B) 25.0N

C) 100.0N

D) 57.7N

E) 43.3N

Exam Body: JAMB