First km/h to m/s:
m/s = km/h / 3.6
m/s = 72 / 3.6
m/s = 20
Now, use the formula:
Vf = Vo + at
Clear t:
t = (Vf - Vo) / a
Replace:
t = (30 m/s - 20 m/s) / 0.5 m/s²
Resolving:
t = 10 m/s / 0.5 m/s²
t = 20 s
It will take <u>20 seconds.</u>
Answer:
Primero, definimos el desplazamiento como la distancia entre la posición final y la posición inicial.
Así, si comenzamos abajo, luego subimos la escalera, y luego bajamos, la posición final y la posición inicial serán la misma
por lo que el desplazamiento es igual a cero.
La medida recorrida es el espacio total recorrido.
Es decir, si entre el principio y el final de la escalera hay una distancia D.
La persona que sube y baja, recorre esta distancia dos veces.
Entonces cuando una persona sube y baja la escalera, la medida de su trayectoria será 2*D.
Charge on can A is positive.
Charge on can C is negative.
Punctuation and capitalization are very useful things to pay attention to and this question would be a lot easier to understand if you had actually used both capitalization and punctuation. If I'm understanding the question, you have 3 metal can that are insulated from the environment and initially touching each other in a straight line. Then a negatively charged balloon is brought near, but not touching one of the cans in that line of cans. While the balloon is near, the middle can is removed. Then you want to know the charge on the can that was nearest the balloon and the charge on the can that was furthermost from the balloon.
As the balloon is brought near to can a, the negative charge on the balloon repels some of the electrons from can a (like charges repel). Some of those electrons will flow to can b and in turn flow to can c. Basically you'll have a charge gradient that's most positive on that part of the can that's closest to the balloon, and most negative on the part of the cans that's furthest from the balloon. You then remove can B which causes cans A and C to be electrically isolated from each other and prevents the flow of elections to equalize the charges on cans A and C when the balloon is removed. So you're left with a deficiency of electrons on can A, so can A will have a positive overall charge, and an excess of electrons on can C, so can C will have a negative overall charge.
Explanation:
it will not change it's motion because it's force is less than the force applied
