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Lo.Lee.Ta.
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Variable formula question... Why does W2 = 24W1?
1. "To accelerate a certain car from rest to the speed v requires the work W1. The
work needed to accelerate the car from v to 5v is W2. Which of the following is correct?"
2. The only forumulas I can think of that deal with work are:
W = Fd
F = ma
a = v/t
...So if you tried to replace the F with velocity terms, you could get:
W1 = m(v/t)d
...Now they say that W2 = [m(5v/t)d] - [m(v/t)d]
They say W2 is the the work needed to accelerate v *TO* 5v, so is that right...?
So W2 = m(4v/t)d, yes? :/
So, if I switch the v/t back to force, then:
W2 = m(4a)(d)
W2 = (F/4)(d)
So W1 = (F)(d) and W2 = (F/4)(d)
Or, 4W2 = Fd = W1
So, it seems like 4W2 = W1 BUT THIS IS COMPLETELY NOT RIGHT!
=_= I don't get this problem at all! Help me, somebody!
The answer's supposed to be W2 = 24W1 !
UGH!
Thank you!
1. "To accelerate a certain car from rest to the speed v requires the work W1. The
work needed to accelerate the car from v to 5v is W2. Which of the following is correct?"
2. The only forumulas I can think of that deal with work are:
W = Fd
F = ma
a = v/t
...So if you tried to replace the F with velocity terms, you could get:
W1 = m(v/t)d
...Now they say that W2 = [m(5v/t)d] - [m(v/t)d]
They say W2 is the the work needed to accelerate v *TO* 5v, so is that right...?
So W2 = m(4v/t)d, yes? :/
So, if I switch the v/t back to force, then:
W2 = m(4a)(d)
W2 = (F/4)(d)
So W1 = (F)(d) and W2 = (F/4)(d)
Or, 4W2 = Fd = W1
So, it seems like 4W2 = W1 BUT THIS IS COMPLETELY NOT RIGHT!
=_= I don't get this problem at all! Help me, somebody!
The answer's supposed to be W2 = 24W1 !
UGH!
Thank you!