Answer:
a) 
b) imagen adjunta
Explanation:
a) Primero debemos hacer la conversión de 81 km/h a m/s, esto es 22.5 m/s.
Ahora, usando la ecuacion cinemática, en un movimiento acelerado tenemos:

Queremos encontrar la posición hasta detenerse, osea vf = 0.



b) Para este caso el gráfico se encuentra adjunto.
Espero que te sirva de ayuda!
Kinetic Energy = (1/2) mv^2.
m = 57.7 g = 57.7/1000 = 0.00577 kg.
v = 325 m/s.
E = 0.5 * 0.00577 * 325^ 2. Use your calculator.
E = 304.728125 J.
That's the kinetic energy.
Answer:
The metal atoms in the wire can't move, but their outer electrons can. The force pushes those electrons and they move to further parts of the wire, trying to reach the other end. As the electrons move away, new electrons flow into the wire through the battery to take their place.
Explanation:
All of the electromagnetic energy radiated from the sun (and from
other stars) is the product of nuclear fusion in its core.