Answer:
a = 0m/s²
Explanation:
Average acceleration = (change in velocity)/(time it takes). Since the car's change in velocity is zero, its acceleration is zero.
Electric field due to a point charge is given as

here we know that

also the distance is given as

now we will have

so we will have

so above is the electric field due to proton
Answer:0.69
Explanation:
Coefficient of kinetic friction=f/R=61.8/90=0.69