The electric potential V as a function of distance x in metres is given by V= (5x2-10x-9) volt. Calculate the value of electric filed at x= 1m ?
20 v/m
6 v/m
zero
11 v/m
A 500μF capcitor is charged at a steady rate of 100 c/s. The potential difference across the capacitor will be 10v after an interval of :
9s
20s
25s
50s
The ratio of the capacitance of a capacitor with a material filled in the entire space between the plates to the capacitance of the same capacitor with empty space in between the plates is equal to
∈0
∈
∈0∈r
∈r
Which of the following is correct ?
Joule = Coulomb x volt
Joule = Coulomb /volt
Joule = volt/ampere
Joule= volt/metre
Three capacitors of capacitance 3μF, 9μF and 18 μF are connected first in series and then in parallel. The ratio of the equivalent capacities in the two cases is
1:15
15:1
1:1
1:2
Six metallic plates each of surface area of one side A are placed at a distance d from each other. The alternate plates are connected to P and Q. The capacitance of the system between P and Q will be :
∈0A/d
3∈0A/d
5∈0A/d
6∈0A/d
Vandegreff generator is used for :
Charging of batteries
Checking voltmeter markings
Producing very high magnetic fields
Accelerating charged particles
A hollow metal sphere of radius 5cm is charged such that the potential on its surface is 10v. The potential at the centre of the sphere is
10v
same as at a point 10cm away from the surface
same as at a point 25cm away from the surface
When a capacitor of capacitance 4 F and p.d. 100v is dischrged, the energy released in joules will be :
0.2
0.02
0.04
0.05
