2019 - JAMB Physics Past Questions and Answers - page 6
One newton × one meter is equal to ___
One water
One Joule
One ampere
One kilogram
A microscope is focused on a mark on a table, when the mark is covered by a plate of glass 2m thick, the microscope has to be raised 0.67cm for the mark to be once more in focus. Calculate the refractive index.
1.52
1.68
2.58
1.82
R = th = 2cm, d = 0.67cm
| n | = | R
A |
= | R
R.d |
= | 2
2-0.67 |
= | 1.52 |
n = 1.52
Radio waves belongs to the class of ware whose velocity is about
340m/s
3 × 10\(^{6}\) m/s
3 × 10\(^{8}\) m/s
3 × 10\(^{-8}\) m/s
A single force which produces the same effect as a set of forces acting together at a point is known as the
component
equilibrant
resultant
resistant
Resultant of forces is the vector representation of multiple forces.
Which of the following statement about the electromagnet shown above is correct?
when the current flows from A to B, the end A will be in north pole
when the current flows from A to B, the end A will be south pole
when the current flows from A to B, the end B will be north pole
none of the above
Calculate the velocity ratio of a screw jack of pitch 0.2cm if the length of the tommy bar is 23cm
230\(\pi\)
23\(\pi\)
70\(\pi\)
140\(\pi\)
Given than:
P = 0.2cm
L = r = 23cm
| Velocity Ratio, VR | = | 2πr
P |
= | 2πL
P |
= | 2π×23
0.2 |
= | 230π |
VR = 230π
The Earth's magnetic equator passes through Jos in Nigeria. At Jos, the
- angle of dip is zero at the magnetic equator
- angle of variation is the same as angle of declination.
The Earth's magnetic equator passes through Jos in Nigeria. At Jos, the
angle of variation is zero
magnetic declination is 90
angle of dip is zero
horizontal component at the Earth's field is zero
Because the angle of dip is zero at the magnetic equator and angle of variation is the same as angle of declination.
A car moving at 20m/s with its horn blowing (f = 1200Hz) is chasing another car going at 15m/s. What is the apparent frequency of the horn as heard by the driver being chased?
1.22KHz
2.40KHz
8.12KHz
1.22Hz
| f\(_1\) | = | f(v - v\(_o\))
v - v\(_s\) |
= | 1200(340 - 15)
340 - 20 |
= | 1.22KHz |
Any line or section taken through an advancing wave in which all the particles are in the same phase is called the
wavelength
wave coast
wave trough
wave front
Wavefront is a surface associated with a propagating wave and passing through all points in the wave that have the same phase. It is usually perpendicular to the direction of propagation