The average speed of the car for the entire trip can be calculate by using:

where S is the total distance covered by the car, and t is the total time taken.
The total distance travelled by the car is:

while the total time taken is:

so, the average speed of the car is:

so, the correct answer is (3) 85 km/h.
Answer:
A) coil A
Explanation:
According to Faraday, Induced emf is given as;
E.M.F = ΔФ/t
ΔФ = BACosθ
where;
ΔФ is change in magnetic flux
θ is the angle between the magnetic field, B, and the normal to the loop of area A
A is the area of the loop
B is the magnetic field
From the equation above, induced emf depends on the strength of the magnetic field.
Both coils have the same area and are oriented at right angles to the field.
Coil A has a magnetic field strength of 10-T which is greater than 1 T of coil B, thus, coil A will have a greater emf induced in it.
Answer:

Explanation:
As we know that magnetic field due to torroid is given as

this is approximately constant magnetic field along the axis of the torroid
now the flux linked with one coil of the torroid is given as


now total flux of N number of coils is given as

now we know that self inductance is the property of coil in which flux of the coil will link with the current in the coil
So we know that


Answer:
Positive velocity and negative acceleration
Explanation:
An object moving in the positive direction has a positive velocity.
An object that's slowing down while moving in the positive direction has a negative acceleration.
Use stronger magnets
increase current
push magnets closer to coil
adding more sets of coils