Answer:
The speed of the stone before it hit the river 3.00 sec later. Let v is the velocity at that instant is 45 m/s.
Explanation:
Given that, a child threw a stone straight down off a high bridge.
Initial velocity of the stone, u = 15 m/s
We need to find the speed of the stone before it hit the river 3.00 sec later. Let v is the velocity at that instant. When it come down, it is moving under the action of gravity. Using equation of motion as :
So, the speed of the stone before it hit the river 3.00 sec later. Let v is the velocity at that instant is 45 m/s.
Answer:
b. electrons drift slowly toward the positive end of the wire
Explanation:
Motion of electrons constitutes current. According to Ohm's law, the current in the wire is directly proportional to the potential difference across the two ends of the wire.
I ∝ V
⇒V = I R
When potential difference is put, the electrons towards the positive end. Thus, option b is correct.
Answer:
Energia cinetica=187.5 [J]
Explanation:
La energia cinetica se define por medio de la siguiente ecuacion:
Debemos convertir las unidades de kilómetros por hora a metros por segundo
Reemplazamos en la ecuacion de energia cinetica.
D. because they aren't mixed up evenly
Answer:
Explanation:
The distance of Earth from the Sun is and of Mars from the Sun is . Let assume that both planets have circular orbits. The centripetal accelaration can be found by using the following expression:
Since planet has translation at constant speed, this formula is applied to compute corresponding speeds:
Earth:
Mars:
Now, centripetal accelarations can be found:
Earth:
Mars:
The ratio of Earth's centripetal acceleration to Mars's centripetal acceleration is: