Question 1.
- mass = 4500 kg
- potential energy (p.e) = 67500 J
now, we know :
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note : if we take acceleration due to gravity as 9.8, then height = 1.53 m
Question 2.
- mass = 4500 kg
- kinetic energy = 63000 j
we know,
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or
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The answer is the first option. The one about doing your best. trust me I read the book today!
# 7 the answer is 4) because you need opposites in order to attract
# 8 I'm going to guess it is 4) because electricity is needed in order a light bolt to work.(don't take my word for this one I'm not sure but, the other answer are correct)
# 9 the answer is 4) because the comb dose collect negative charges from the hair in order to make the hair have positive charge.
Hope this helped : )
This problem is to let you practice using Newton's second law of motion:
Force = (mass) x (acceleration)
-- The airplane's mass when it takes off (before it burns any of its load of fuel) is 320,000 kg.
-- The force available is (240,000 N/per engine) x (4 engines) = 960,000 N.
-- Now you know ' F ' and ' mass '. Use Newton's second law of motion to calculate the plane's acceleration.