Answer:
an instrument for measuring an electromotive force by balancing it against the potential difference produced by passing a known current through a known variable resistance.
Answer:
The correct answer is "0.32 mL".
Explanation:
The given values are:
Density of gold bar,
d = 19.3 g/mL
Mass of gold bar,
m = 6.3 grams
Now,
The volume will be:
⇒ 
or,
⇒ 
On substituting the values, we get
⇒ 
⇒ 
Answer:
center of mass of the two masses will lie at x = 2.52 cm
center of gravity of the two masses will lie at x = 2.52 cm
So center of mass is same as center of gravity because value of gravity is constant here
Explanation:
Position of centre of mass is given as

here we have




now we have



so center of mass of the two masses will lie at x = 2.52 cm
now for center of gravity we can use

here we have




now we have



So center of mass is same as center of gravity because value of gravity is constant here
The sound was repeated because of the phenomenon of echo. The speed of sound in the metal is 800 m/s.
Echo results from the reflection of sound waves. The reason why a sound may be heard twice owes to the phenomenon of reflection which leads to echo.
To determine the speed of sound in the metal;
Length of metal = 1000 m
Time taken between the two sounds = 2.5 s
Using the formula;
V = 2d/t
V = 2(1000)/2.5
V = 800 m/s