Answer:
a
The magnitude of the force is 
The direction is from south to north i.e upward
b
The magnitude of the force is 
The direction is towards the west
c
The magnitude of the force is 
the direction of the magnetic field is parallel to the direction of the current (south to north ) hence the direction in 0 in comparison to the direction of the current
d
From the value of force we got the answer to this question is No
Explanation:
Generally magnetic force is mathematically represented as

Where the B is the magnitude of the magnetic field which is given as

is the current with a value of 
L is the length of the wire given as 
Substituting the value


For the first case where the current is moving from west to east and we are told that the magnetic field is from south to north the according to Fleming's right hand rule the force(exerted by earths magnetic field ) would be moving from south to north (i.e upward)
For the second case where current is moving vertically upwards the direction of the force is to the west according to Fleming's right hand rule
Explanation:
This problem bothers elastic collision.
Given data
Mass m1= 25kg
Initial velocity u1= 5m/s
Final velocity v1= 1.5m/s
Mass m2= 35kg
Initial velocity u2=?
Final velocity v2 = 4.5m/s
A. To find the initial velocity of the 35kg car, let us Apply the principle of conservation of energy
m1u1+m2u2= m1v1+m2v2
25*5+ 35*u2= 25*1.5+ 35*4.5
125+35u2= 37.5+157.5
125+35u2=195
35u2= 195-125
35u2= 70
u2= 2m/s
The initial velocity is 2m/s
B. Totally not kinetic energy before impact
KE= 1/2m1u1²+ 1/2m2u2²
KE= (25*5²)/2+ (35*2²)/2
KE= 625/2 +140/2
KE= 312.5+70
KE= 382.5J
Total kinetic energy after impact
KE=1/2m1v1²+ 1/2m2v2²
KE= (25*1.5²)/2 +(35*4.5²)/2
KE= 56.25/2 +708.75/2
KE=28.125 +354.375
KE= 382.5J
We can see that energy is conserved
Kinetic energy before and after impact remains unchanged
If length of the cylinder is doubled, its volume becomes twice the initial volume(
Volume of cylinder = π
) and as a result density becomes half the initial density. Hope this helps!
Answer: It wouldn't be as modern as today is we would be back to using oil and other things from back then there wouldn't be cars everything would be less machined.