Answer 1) : 62.5 km/hour is the average velocity of the train.
2) The final velocity of the car at the end of 75 m is 14.69 m/s
Explanation:
1) Displacement of the train = 100 km + 150 km = 250 km
Total time train took =1 hour 15 min+ 45 min + 2 hours = 240 min = 4 hours
Average velocity=
62.5 km/hour is the average velocity of the train.
2) The acceleration of the car, a= 1.2 
Distance covered by the car,s = 75 m
Initial velocity of the car ,
= 6 m/s
Final velocity of thre car ,
=?
Using third equation of motion:
The final velocity of the car at the end of 75 m is 14.69 m/s
part 1
mass = ρ x V
mass = 1739 kg/m³ x 3.8 km³ = 6608.2 kg
PE (potential energy)= mgh
PE = 6608.2 kg x 9.81 x 403
PE = 2.61 x 10⁷ J
part 2
megaton of TNT (Mt) =4.2 x 10¹⁵ J
convert PE to Mt:
2.61 x 10⁷ J : 4.2 x 10¹⁵ J = 6.21 x 10⁻⁹ Mt
Answer: s=d/t= 500/7.0=71.42 m/s
Explanation:
Answer:
615 J
Explanation:
internal energy (U) = 504 J
heat lost (q) = 111 J = - 111 J (negative sign is because heat is lost)
work done = 222 J
what is the final energy in the system
total energy = final energy - initial energy
final energy = total energy + initial energy
where
initial energy = 504 J
total energy = 222 - 111 = 111 J
final energy = 504 + 111 = 615 J
