The magnetic field strength in a coil is directly proportional to the number of turns, or loops, in the coil.
Therefore, when there are four loops instead of one, the magnetic field strength has increased four times, making it harder to push the magnet in.
Answer:
option A
Explanation:
given,
depth of the sea level = 10 m
g = 10 m/s²
Pressure underwater = ?
we know,
P = ρ g h
where ρ is the density of water which is equal to 1000 kg/m³
h is the depth of sea level
P = ρ g h
P = 1000 x 10 x 10
P = 100000 Pa
P = 100 kPa
Hence, the correct answer is option A
W = 1/2k*x^2.
k = spring constant = 2500 n/m.
x = distance = 4 cm = 0.04m (convert to same units).
W = 1/2(2500)(0.04)^2 = 2J.
Answer:395.6 m/s
Explanation:
Given
mass of bullet 
mass of wood block 
Length of string 
Center of mass rises to an height of 
initial velocity of bullet 
let
and
be the velocity of bullet and block after collision
Conserving momentum
-------------1
Now after the collision block rises to an height of 0.38 cm
Conserving Energy for block
kinetic energy of block at bottom=Gain in Potential Energy




substitute the value of
in equation 1


A falling skydiver opens his parachute. A short time later, the weight of the skydiver-parachute system and the drag force exerted on the system are equal in magnitude. The following statements predicts the motion of the skydiver at this time
<u>The skydiver is moving downward with constant speed.</u>
Explanation:
Immediately on leaving the aircraft, the skydiver accelerates downwards due to the force of gravity. There is no air resistance acting in the upwards direction, and there is a resultant force acting downwards. The skydiver accelerates towards the ground.
The forces acting on a falling leaf are : gravity and air resistance.
The net force and the acceleration on the falling skydiver is upward.
An upward net force on a downward falling object would cause that object to slow down. The skydiver thus slows down.
As the speed decreases, the amount of air resistance also decreases until once more the skydiver reaches a terminal velocity.
<u>A skydiver falling at a constant speed opens his parachute. When the skydiver is falling, the forces are unbalanced.</u>