Answer:
4.2s
Explanation:
Given parameters:
Power = 2190W
Mass of box = 1.47 x 10⁴g
distance = 6.34 x 10⁴mm
Unknown:
Time = ?
Solution:
Power is the rate at which work is done;
Mathematically;
Power =
Time =
Work done = weight x height
convert mass to kg;
100g = 1kg;
1.47 x 10⁴g = 14.7kg
convert the height to m;
1000mm = 1m
6.34 x 10⁴mm gives 63.4m
Work done = 14.7 x 9.8 x 63.4 = 9133.4J
Time taken = = 4.2s
Answer:
4 A
Explanation:
The relationship between current, voltage and resistance in a circuit is given by Ohm's law:
where
V is the voltage
R is the resistance
I is the current
The equation can also be rewritten as
from which we see that the current is inversely proportional to the resistance, R.
In this problem, the initial current is I = 8 A. Then the resistance is doubled:
R ' = 2R
So the new current is
so the current is halved.
Answer:
The specific question is not stated, however the general idea is given in the attached picture. The electric field in each region can be found by Gauss’ Law.
at r < R:
Since the solid sphere is conducting, the total charge Q is distributed over the surface, and the electric field inside the sphere is zero.
E = 0.
at R < r < 2R:
The electric field can be found by Gauss’ Law as in the attachment. The green pencil shows this exact region.
at 2R < r:
The electric field can again be found by Gauss’ Law, the blue pencil shows the calculations for this region.
Explanation:
Gauss’ Law is straightforward when applied to spheres. The area of the sphere is , and the enclosed charge is given in the question as Q for the inner sphere, and 2Q for the whole system.
