Answer:
book speed is 3.99 m/s
Explanation:
given data
mass m = 490 g = 0.490 kg
compressing x = 7.10 cm = 0.0710 m
spring constant k = 1550 N/m
to find out
book speed
solution
we know energy is conserve so
we can say
loss in spring energy is equal to gain in kinetic energy
so
..................1
put here value
v = 3.99 m/s
so book speed is 3.99 m/s
Answer:
magnetic trains works at the principle of repel on of the advantage is that they are fast and dont really need diesel
A. 320 g
B. 160 g
C. 80 g
D. 40 g