Answer:
The number of turns in the second coil is more than the coil 1.
Explanation:
The magnetic field lines are the imaginary path on which an isolated north pole moves if it is free to do so.
The tangent at any point to the magnetic field line, gives the direction of magnetic field at that point.
More be the crowd ness of magnetic field lines more is the strength of magnetic field.
Here the crowd ness of magnetic field lines is more in figure 2 , so the magnetic filed in figure 2 is more than 1. It shows that the number of turns in the second coil is more than the 1 and also the current in the coil 2 is more than 1 .
Answer:
The downward force of gravity and the force exerted by the air.
Explanation:
Gravity, in a Newtonian Framework, acts at distance, so, the ball doesn't has to be connected to Earth to feel its gravitational pull (as we know by experience).
The racket only can exert a force in the ball when is touching it, so, once the ball has left the contact with the racket, there is no force by the "hit".
The air is always touching the ball on the atmosphere (even when physicist pretend that is not). So, there is drag from the wind, and a buoyant force exerted by the air over the ball at every time.
Answer:
The speed of the block when it has returned to the bottom of the ramp is 6.56 m/s.
Explanation:
Given;
mass of block, m = 4 kg
coefficient of kinetic friction, μk = 0.25
angle of inclination, θ = 30°
initial speed of the block, u = 5 m/s
From Newton's second law of motion;
F = ma
a = F/m
Net horizontal force;
∑F = mgsinθ + μkmgcosθ

At the top of the ramp, energy is conserved;
Kinetic energy = potential energy
¹/₂mv² = mgh
¹/₂ v² = gh
¹/₂ x 5² = 9.8h
12.5 = 9.8h
h = 12.5/9.8
h = 1.28 m
Height of the ramp is 1.28 m
Now, calculate the speed of the block (in m/s) when it has returned to the bottom of the ramp;
v² = u² + 2ah
v² = 5² + 2 x 7.022 x 1.28
v² = 25 + 17.976
v² = 42.976
v = √42.976
v = 6.56 m/s
Therefore, the speed of the block when it has returned to the bottom of the ramp is 6.56 m/s.
Answer:
C
Explanation:
He was using visual clues to read the signs.
the moon rock since its gravity is 10x lighter than earths