Heat transfer in the surrounding without a material medium is possible through?
Conduction
Convection
Radiation
Expansion
Correct answer is C
Conduction, convection of heat or electricity through a material medium is required but radiation requires no material medium for heat transfer
Electromagnetic devices
Magnetic relay device
None at all
Sextant
Correct answer is B
Magnetic relay device :is the device that controls a circuit (i.e one circuit )if a current in the second circuit is large or dangerous
1, – 2, 1
1, 2, – 2
1, 1, –2
2, 2, 1
Correct answer is B
Work (w) = Force (f) × Distance (d)
Note: f = ma = mass × acceleration
= mass ×acceleration ×distance
= kg ×ms–2 × m
= kg m2 5–2
(Note: the dimension of kg = M, M = L & S = T)
Work = ML2 T–2 = Ma Lb Tc
i.e. Ma Lb Tc = as 1, b = 2, c = –2
The value of a, band c = 1, 2, –2
The compressed regions and the space-out regions in longitude wave are refers to as
Compression and Rarefaction
Comparison and Explosion
Reflection only
Refraction only
Correct answer is A
The vibrating particles behave like a spiral spring with a series of compression region and space–out region.
A member of the crew of a SPACESHIP experiences weightlessness in a space when they
Fall freely from the earth’s gravitational field
Is walking on the planet
In between the sun and the earth
Holding anything in space is negative
Correct answer is A
Weightlessness:– The state of being free from the effects of gravity. (zero gravity)