First of all, we need to calculate the magnetic field generated by the wire at a distance r=3.90 cm=0.039 m, which is given by:
where I=8.60 A is the current. Substituting numbers in the equation, we find
And now we can calculate the force exerted on the electron, which is given by:
where 
is the charge of the electron and 
is its speed. Substituting data in the formula, we find
Newton's law of gravity does not explain WHY objects exert gravitational force.
Answer:
d.
Explanation:
Since, the capacitance( decreases )
therefore voltage between the plates(increases ).
Hence, option d is correct.
C =εA/d.
d is doubled, therefore C decrease ( inverse relation).
Answer:
Explanation:
We shall apply conservation of mechanical energy .
initial kinetic energy = 1/2 m v²
= .5 x m x 12 x 12
= 72 m
This energy will be spent to store potential energy . if h be the height attained
potential energy = mgh , h is vertical height attined by block
= mg l sin20 where l is length up the inclined plane
for conservation of mechanical energy
initial kinetic energy = potential energy
72 m = mg l sin20
l = 72 / g sin20
= 21.5 m
deceleration on inclined plane = g sin20
= 3.35 m /s²
v = u - at
t = v - u / a
= (12 - 0) / 3.35
= 3.58 s
it will take the same time to come back . total time taken to reach original point = 2 x 3.58
= 7.16 s
Answer:
Option (3)
Explanation:
Formula used to calculate acceleration is,
F = ma
Where F = force exerted on a mass
m = mass
a = acceleration due to force exerted on the mass
Option (1),
When F = 100 N and m = 100 kg
100 = 100a
a = 1 m per sec²
Option (2)
For F = 1 N and m = 100 kg
1 = 100a
a = 
a = 0.01 m per sec²
Option (3)
For F = 100 N and m = 1 kg
100 = 1(a)
a = 100 m per sec²
Option (4)
For F = 1 N and m = 1 kg
1 = 1(a)
a = 1 m per sec²
Therefore. acceleration in Option (3) is the maximum.
