Answer:A
Explanation:
Initial velocity, u = 2m/s
Final velocity, v = 4m/s
Distance covered, s = 12m
Acceleration, a = ?
Using
v² = u² + 2as
2as = v² - u²
a = v²-u²/2s
a = 4²-2²/2 x 12
a = 16-4/24
a = 12/24
a = 0.5m/s²
Answer:9.51 m/s
Explanation:
Given
Window is 4.35 m above ground
time taken=1.2 s
Let u be the initial velocity of keys
where s=distance traveled
u=initial velocity
t=time taken
g=acceleration due to gravity
(b)velocity of keys just before they were caught
v=u+at
v=-2.26 m/s
Here negative sign indicates downward motion of keys
More energy is released in nuclear reactions than in chemical reactions; this is because in nuclear reactions, mass is converted to energy. Nuclear energy released in nuclear fission and fusion is several 100 million times as large as an ordinary chemical reaction like the combustion process. The reason why nuclear energy release so much energy is because tremendous amounts of energy is released at one time. The nuclei in a nuclear reaction undergo a chain reaction, causing the neutrons to move extremely fast and release high amounts of energy.
