1) A train is accelerating at a rate of 2.0 km/hr/s. If its initial velocity is 20 km/hr, what is its velocity after 30 seconds?
2) A runner achieves a velocity of 11.1 m/s 9 s after he begins. What is his acceleration?
What distance does he cover?
2006-12-13 11:15:25 · 5 answers · asked by Red 1 in Science & Mathematics ➔ Physics
1.V= A(t) + Vo
convert seconds to hour.
(2)(1/120) + 20=20.167
2.V=A(t) + Vo
11.1=A(9) + 0
A=(11.1/9)m/s2
2006-12-13 11:23:30 · answer #1 · answered by jpferrierjr 4 · 0⤊ 0⤋
v(f) = v(i) + a.t
= 20 [km/hr] + 2 [km/hr.s] x 30
=20+60
= 80 km/hr
second one:
11.1 = 0 + a(9)
a= 11.1/9
2006-12-13 11:19:24 · answer #2 · answered by Anonymous · 0⤊ 0⤋
...and for the second part of 2), the distance traveled is
.5*a *t² = .5*(11.1/9)*9² = 49.95 m
2006-12-13 11:23:12 · answer #3 · answered by Steve 7 · 0⤊ 0⤋
you could no longer plug in "a million" or "2" or "3" for "s", meaning "one 2nd." "s" is an algebra variable that represents a definite quantity of time. that's not equivalent to the numbers a million or 2 or 3. you could no longer replace something for it, different than "a million/60 minute", and so on. The equation you're in seek of for is acceleration = substitute in velocity / time.
2016-12-11 08:35:24 · answer #4 · answered by scheiber 4 · 0⤊ 0⤋
No man is correct !
2006-12-13 11:24:12 · answer #5 · answered by Dave S 3 · 0⤊ 0⤋