B I think hope this helps
Just ignore the horizontal component
if you have a vertical displacement of 15m, 0ms^1 initial velocity, end velocity is ignored, we know the acceleration due to gravity as 9.81ms^2 so we can work out the time using SUVAT
S=15
U=0
V=?
A=9.81
T=?
S=UT + 0.5 AT^2
UT=0
therefore,
S=0.5AT^2
rearrange to:
T=SQR (2S/A)
T = 1.75 seconds
Answer:
<em>The speed of the water bottle at impact with the street is 49 m/s</em>
Explanation:
<u>Free Fall Motion
</u>
A free-falling object falls under the sole influence of gravity. Any object that is being acted upon only by the force of gravity is said to be in a state of free fall. Free-falling objects do not experience air resistance.
If an object is dropped from rest in a free-falling motion, it falls with a constant acceleration called the acceleration of gravity, which value is
.
The final velocity of a free-falling object after a time t is given by:
vf=g.t
The water bottle dropped by Jamie takes t=5 seconds to impact the ground, thus its speed at that moment is:
vf= 9.8*5
vf = 49 m/s
The speed of the water bottle at impact with the street is 49 m/s
On axis of the dipole the electric field is given by



now if we approximate above equation

now we will find the ratio of these two

put r = 3d



<em>so above is the ratio of two field</em>
Answer: Speed of galaxy B with respect to galaxy A = 0.8
Speed of galaxy C with respect to galaxy A = 1.4
Explanation:
Let the speed of galaxy A with respect to galaxy B be Vab & it is equal to Va - Vb = -0.8
Let the speed of galaxy C with respect to galaxy B be Vcb = Vc - Vb = 0.6
Speed of galaxy B with respect to galaxy A = Vba = Vb - Va = -Vab = -(-0.8) = 0.8
Speed of galaxy C with respect to galaxy A = Vca = Vc - Va
But from above, Vc - Vb = 0.6; Vc = 0.6 + Vb
And Va - Vb = -0.8; Va = -0.8 + Vb
Vca = Vc - Va = 0.6 + Vb - (-0.8 + Vb) = 0.6 + Vb + 0.8 - Vb = 0.6 + 0.8 = 1.4
(Solved)