Physics Questions and Answers
If you want to learn more about the nature and properties of matter and energy or you're simply preparing for a Physics exam, these Physics past questions and answers are ideal for you.
If you want to learn more about the nature and properties of matter and energy or you're simply preparing for a Physics exam, these Physics past questions and answers are ideal for you.
Voltmeter
Meter rule
Galvanometer
Potentiometer
Correct answer is D
Voltmeter: an instrument for measuring electric potential in volts
Galvanometer: it is a device used to indicate direction of a small electric current
Potentiometer: is a device for measuring or comparing e.m.fs of cells
Meter rule: measuring a distance at different points
2 m/s
4 m/s
12 m/s
14 m/s
Correct answer is C
d = y, s = 6 m/s (The Man & Plane Mirror)
d – δy, s = (5 &ndash ;6) m/s (The Man and Image)
d2 ÷ s1 = d2 ÷ s2, y ÷ 6 = 2y ÷ s + 6
Y (s + 6) = 2y × 6
s + 6 = 12
So = 12 – 6 = 6
Since S + 6 = 0
Then, S = 6 (substitute the value of S i.e S = 6)
Into S + 6 = 0
∴So = S + 6 = 6 + 6 = 12 m/s
∴ S = 12 m/s
Efficiency of a transformer is equal to
Efficiency of transformer = (secondary coil ÷ primary coil) × 100%
Efficiency of transformer = (mechanical advantage ÷ velocity ratio) × 100%
Efficiency of a transformer = (Number of turns in the secondary coil ÷ Number of turns in the primary coil) × 100%
Efficiency of a transformer = (power developed in the secondary coil ÷ power supplied to the primary coil) × 100%
Correct answer is D
Efficiency of a transformer = (power developed in the secondary coil ÷ power supplied to the primary coil) × 100%
Which one of the following is a vector quantity?
Temperature gradient
Mass
Work
Time
Correct answer is A
Temperature gradient(Tg) = DT ÷ L = T2 – T1 ÷ L
i.e– it is the ratio of an increment in temperature to the length
Hence, Temperature gradient (Tg) has defined direction alongside with magnitude
And it is a vector quantity
Mass, work & Time are scalar quantity