### Physics Past Questions

4596

(a) You are provided with a battery, an ammeter, a voltmeter, a resistance box, a key and connection wires.

(i) Set up circuit as shown in the diagram above.

(ii) With the key opened, measure and record the e.m.f. E$$_o$$ of the battery

(iii) With the key closed, select the resistance R=1 on the resistance box. Read and record the current, 1Ω.

(iv) Evaluate I$$^{-1}$$.

(v) Repeat the procedure for five other values of R=2Ω,3Ω, 4Ω, 5Ω, and 6Ω.

In each case, record I and evaluate I$$^{-1}$$ results.

(vii) Plot a graph with R on the vertical axis and I$$^{-1}$$ on the horizontal axis.

(Viii) Determine the slope, s, of the graph.

(ix) Determine the intercept C, On the vertical axis.

(x) State two precautions taken to ensure accurate results.

(b)(i) Define potential difference in an electric field.

(ii) A piece of resistance wire of diameter 0.2 mm and length 25 cm has a resistance of 7Ω. Calculate the resistivity of the wire of the battery. [ π = 22\7]

WAEC 2021
4597

The area under a force-time graph represents--------

• A. change in kinetic energy
• B. change in momentum
• C. change in work done
• D. change in internal energy
WAEC 2022
4598

From the principle of flotation, a body sinks in a fluid until it displace a quantity equal to its own?

• A. density
• B. mass
• C. weight
• D. volume
WAEC 2022
4599

The length of a simple pendulum is increased by a factor of four. By what factor is its period increase?

• A. 0.5$$\pi$$
• B. 2
• C. 2$$\pi$$
• D. 4
WAEC 2022
4600

The linear expansivity, $$\alpha$$, and cubic expansivity, $$\gamma$$, of a material are related by the equation?

• A. $$\gamma$$=a
• B. $$\gamma$$=3$$\alpha$$
• C. $$\gamma$$=2a
• D. $$\gamma$$=$$\frac{1}{3} \alpha$$
WAEC 2022