Pressure = Force/ Area = 3000/2 = 1500 pascal.
Answer:
b. Cho biết tốc độ của xe là 4m/s. Hãy tính tốc độ góc của điểm trên vành ngoài bánh xe.
Explanation:
#CarryOnLearning
Potential energy decreases and kinetic energy increases.
Potential energy is related to the height, since the wagon is going downhill, height decreases and potential energy decreases.
Kinetic energy is related to the speed, since the wagon is speeding up, kinetic energy increases.
Answer:
d. 37 °C
Explanation:
= mass of lump of metal = 250 g
= specific heat of lump of metal = 0.25 cal/g°C
= Initial temperature of lump of metal = 70 °C
= mass of water = 75 g
= specific heat of water = 1 cal/g°C
= Initial temperature of water = 20 °C
= mass of calorimeter = 500 g
= specific heat of calorimeter = 0.10 cal/g°C
= Initial temperature of calorimeter = 20 °C
= Final equilibrium temperature
Using conservation of heat
Heat lost by lump of metal = heat gained by water + heat gained by calorimeter

Explanation:
According to the Faraday-Lenz law, a conductive ring generates an induced current due to the change in the magnetic flux caused by the motion of the bar magnet. This induced current generates a magnetic field opposite to the magnetic field of the bar, generating an upward force that opposes the weight of the bar magnet, Therefore, it does not move as a freely falling object.