Answer:
1- For the track B. The potential energy is the same for the two cars, but because of the slope of the track, the car B earn kinetic energy faster. The gravitation acceleration of the cars will be g•sinθ, and the angle of the track B will have a bigger value for sinθ
2- The conservation of energy applies because the roller coaster is a closed track. When a car climb the track, it earn GPE, which is given by mgh, when it get down in the track, it transform GPE in KE, which is given in 1/2mv².
3-
Position of car (m) GPE KE GPE + KE
top (30m) 60000 0 60000
bottom (0m) 0 60000 60000
halfway down (15m) 30000 30000 60000
three-quarters way down 15000 45000 60000
Answer:
240 Ω
Explanation:
Resistance: This can be defined as the opposition to the flow of current in an electric field. The S.I unit of resistance is ohms (Ω).
The expression for resistance power and voltage is give as,
P = V²/R.......................... Equation 1
Where P = Power, V = Voltage, R = Resistance
Making R the subject of the equation,
R = V²/P.................... Equation 2
Given: V = 120 V, P = 60 W.
Substitute into equation 2
R = 120²/60
R = 240 Ω
Hence the resistance of the bulb = 240 Ω
Explanation:
Given that,
A person walks 9.0 km directly east and then turns left and heads directly north for 12.0 km.
We need to find his displacement from the starting position.
We know that,
Displacement = shortest path covered

For direction,

Hence, this is the required solution.
Answer:
4 m/s²
Explanation:
When the elevator is 1 m below point of contact , compression will be 1 m.
Restoring force in the spring will be 10600 N. Friction force of 17000N will also act in upward direction . The weight of 2000 x 9.8 N will act downwards
Force in down ward direction = 2000 x 9.8
= 19600 N
Force in upward direction
= 10600 + 17000
= 27600 N
Net force in upward direction
= 27600 - 19600
= 8000 N
Acceleration in upward direction
= 8000 / 2000
= 4 m/s²