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3 years ago

1.) A ball is thrown horizontally from the top of a building. What is the vertical velocity of the ball after 1 second?

Physics

2 answers:

MatroZZZ [7]3 years ago

7 0

Answer:

B. 9.8 m/s
A. 0 m/s²
C. 45°
B. 70°
D. uniformly accelerated motion

Explanation:

u=0m/s

v=?

a=9.8m/s²

t=1sec

now

we have

v=u+at

v=0+9.8*1

v=9.8m/s

angle is measured in sin and cos angle where maximum angle's value is gained by 45°

we have

range

R= $\frac{u²sin2\theta}{g}$

For

angle =20°

R1= $\frac{u²sin2*20}{g}$ .......[1]

another angle be $\theta$

R2= $\frac{u²sin2\theta}{g}$ .......[2]

since R1=R2

By comparing we get

Sin40=Sin( $2\theta$ )

Sin(180-40)=Sin( $2\theta$ )

140= $2\theta$

$\theta$ =70°

BARSIC [14]3 years ago

6 0

9.8
zero
45
not sure - 70
Uniform accelerated motion

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