JAMB Physics Past Questions & Answers - Page 133

661.

The velocity time graph above describes the motion of a particle between two points P and Q. What is the distance between P and Q?

A.

17.0m

B.

18.0m

C.

22.5m

D.

30.0m

Correct answer is B

distance = area under the graph.

= \(\frac{1}{2}\times 1 \times 4 ) + \frac{1}{2} \times (4+6)\times 1) + (6 \times 1.5) + (\frac{1}{2}\times(2 + 6)\times 0.5)\)

662.

fig 1 is a graph of force against extension for a spiral spring, the force constant of the spring is given by the

A.

slope of the linear portion of the graph

B.

length of the linear portion of the graph

C.

area under the linear portion of the graph

D.

area under the entire graph

Correct answer is A

No explanation has been provided for this answer.

665.

fig 4 represents a block-and-tackle pulley system on which an effort of W newtons supports a load of 120.0N if the efficiency of the system is 40% then the value of W is

A.

28.0N

B.

48.0N

C.

50.0N

D.

288.0N

Correct answer is C

Efficiency = \(frac{M.A×100}{V.R}\)
V.R = 6
40= \(frac{M.A×100}{6}\)
M.A = \(frac{6 ×40}{100}\)
M.a=2.4
M.A= \(frac{L}{E\)
E= \(frac{120}{2.4\)
E= 50