I throw a ball up in the air with some initial velocity v 1 and it stays in the air for some time t 1 . I then throw the ball straight up with velocity v 2 and find that this time it stays in the air for a time t 2 = 2 t 1 . What is v 2 / v 1 ?
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We have
x
=
−
2
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t
2
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0
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(Assuming the ball is thrown from
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When the balls gets back to the ground:
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0
(with
t
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0
) then,
v
1
=
−
2
g
t
1
and
v
2
=
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2
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t
2
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.
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v
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.
v = u + a t
Given that acceleration due to gravity is the same for the two throws, we know that v ∝ t . This means that if you double t , you also double v .
Since t 2 = 2 × t 1 ,
v 2 = 2 × v 1
∴ v 1 v 2 = 2
V=u-gt where u=0unit and g is constant !!
a formula for this case is:
t = s/v
t = time s = distance v = velocity
from above formula, we can take a conclude that if t is become twice bigger than before, then v is become a half of before.
for 1st ball 0=V1-gt1 V1=gt1
for 2nd ball 0=V2-gt2 V2=gt2
V2/V1=t2/t1=2
s=ut+at^{2}/2 s=o we get v=gt/2 hence v2 /v1=t2/t1 =2
If time taken for second ball is half as time taken for first ball then the speed of second ball should be twice as first ball ,
So speed of first ball be anything but it is half as second ball ,
So let the speed of first ball be 1(v1) then the speed for second ball equals to 2 (v2) ,
2(v2) / 1 (v1) = 2..
final velocity(v)=0 unit, v=v(1)-g t(1)...................(1) v=v(2)-g t(2)...................(2) 2/1 then,answer will be 2
when the ball moves up with velocity vi and when it is thrown 2nd time it moves up with velocity v2.the first ball takes time t and 2nd ball takes time t2 which is double so it means its velocity is also double .when we take any number instead of velocity its answer is always 2 like this v2/v1 when we take v2=10 and v1=5 because v2 is double that of v1 then 10/5 becomes equal to 2
yours one is the best answer
for 1st ball 0=v1-gt1 v1=gt1
for 2nd ball 0=v2-gt2 v2=gt2
v2/v1=t2/t1=2
velocity 1st case is (at) in 2nd case is (2at) dividing 2nd by 1st =2.
as t2=2t1 => v2/v1=2t1/t1 => v2/v1=2
u can solve it through......v=u-gt
v2/v1 = t2/t1 ---> v2/v1 = 2t1/t1 = 2 [m/s]. Answer : 2
as we know that this comes under time of ascent so V=-GT V1=-9.81 T(T=T1) V2=-9.81 2T(T2=2T1) V2/V1=-9.81 T/-9.81 2T V2/V1=2
Well,the time and speed are directly proportionals,so if the T2 = 2xT1,we have the conclusion that V2 = 2xV1, so , 2/1 = 2.
for both cases final velocity ie V(f) will be equal to zero for the case 1 V(f)=v1 -gt 0=v1-gt for the case 2 v(f)=v2-g t1 0=v2-2g t1 v1/v2=2
v=u+at. In this case u is 0, thus, v=at thus v is directly proportinal to time. so,T2=2T1. So v2=2V1 v2/v1=2
how u is 0 in this case ?
plz see the question...it stays in d air..so that the final velocity u=0
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The formula for vertical motion up is v t = v 0 − g t
Since the v t is 0 , so the formula becomes v 0 = g t
v 1 = g t 1
Then..
v 2 = g t 2
v 2 = 2 g t 1
So..
v 1 v 2 = g t 1 2 g t 1
v 1 v 2 = 1 2 = 2