Answer:
acceleration, a = 9.8 m/s²
Explanation:
'A ball is dropped from the top of a building' indicates that the initial velocity of the ball is zero.
u = 0 m/s
After 2 seconds, velocity of the ball is 19.6 m/s.
t = 2s, v = 19.6 m/s
Using
v = u + at
19.6 = 0 + 2a
a = 9.8 m/s²
Answer:
Global dependence on fossil fuels has associated social costs.
Explanation:
Increased dependence on fossil fuels reduces their availability. When the demand is high and the availability is low, the price rises. Not every nation would then be able to afford buying fossil fuels at such high costs.
Developing and underdeveloped countries would then be left behind and only the wealthy nations would be able to afford fossil fuel purchase. This would be the immediate impact of global dependence on fossil fuels.
Fossil fuels are mainly coal, petroleum and natural gas. Since fossil fuels are non-renewable in nature over exploitation may lead to fossil fuels getting exhausted.
Answer:
Bad things
Explanation:
Global warming has many terrible effects on people and the earth itself
such as, death, birth defects, asthmea, breathing conditions, increased diseases.
Answer: find the answer in the explanation
Explanation:
When a magnet is placed at the centre of the paper, and the nails are sprinkled on the paper, what will happen to the nails is that, the nails will form a pattern on the paper according to the magnetic field of the bar magnetic pole.
Other phenomena you can observe are:
1.) The nails will align themselves and show some lines of forces which is equivalent to the magnetic field lines
2.) The direction of the line of forces
3.) The strength of the magnetic field pole.
Answer:
Explanation:
According to first law of thermodynamics:
∆U= q + w
= 10kj+(-70kJ)
-60kJ
, w = + 70 kJ
(work done on the system is positive)
q = -10kJ ( heat is given out, so negative)
∆U = -10 + (+70) = +60 kJ
Thus, the internal energy of the system decreases by 60 kJ.
