Kinetic energy = 1/2mv2
= 1/2 x 2 x 3^2
= 9J
11.46 meters
55 km/h = ? m/s
55 km/h × 1000 (meters per km) = 55,000 m/h
55,000 m/h ÷ 3,600 (seconds in an hour) = 15.28 m/s
15.28 m/s × 0.75 s = 11.46 m
<span>The electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation. The "electromagnetic spectrum" of an object is the characteristic distribution of electromagnetic radiation emitted or absorbed by that particular object. Hope this helped.</span>
Explanation:
Given that the first ball is thrown vertically and upward.
since it reaches the throwers hand after 3 seconds, then the time taken to reach maximum height is
= T/2
=3/2
=1.5 seconds
Also, the projection angle for the second ball is 30°
we know that at maximum height vertical velocity is 0
therefore the final velocity of the first ball is
Vy= 0
Also, since the first ball is thrown upward the horizontal velocity is 0
Vx=0
from the first law of motion
Vy=u+at
Vy=0, a= -g
Uy=gt
Uy=9.81*1.5
Uy=14.7m/s
since both reach the same height, they will have the same vertical velocity
Uy= Vo sin∅
Vo=Uy/sin∅
Vo= 14.7/sin 30
Vo=29.4m/s