Answer:
initial velocity=12.31 m/s
Final speed= 16.234 m/s
Explanation:
Given Data
height=5.72 m
distance=13.30 m
To Find
Initial Speed=?
Solution
Use the following equation to determine the time of the stone is falling.
d = vi ×t ½ ×9.8 × t²
Where
d = 5.72m and vi = 0 m/s
so
5.72 = ½× 9.8 ×t²
t = √(5.72 ÷ 4.9)
t=1.08 seconds
To determine the initial horizontal velocity use the following equation.
d = v×t
13.30 = v ×1.08
v = 13.30 ÷ 1.08
v=12.31 m/s
To determine stone’s final vertical velocity use the following equation
vf = vi+9.8×t............vi=0 m/s
vf = 9.8×1.08
vf= 10.584 m/s
To determine stone’s final speed use the following equation
Final speed = √[Horizontal velocity²+Final vertical velocity²]
Final speed = √{(12.31 m/s)²+(10.584 m/s)²}
Final speed= 16.234 m/s
Answer:
C. The voltage drop across the resistor is 2.1V and nothing about the current through the resistor.
Explanation:
When connected in parallel, voltage across the resistances are the same. So if 2.1V was dropped across the LED then 2.1V was also dropped across the resistor. However, this tells us nothing about the current through the resistor. We can find the current across the resistor if we know the resistance of the resistor, but that's about it.
If it were a series connection, then the current would have been the same, but the voltage drop were another story.
Explanation:
Given
Ball is projected horizontally from a building of height 
time taken to reach ground is given by
(b) Line joining the point of projection and the point where it hits the ground makes an angle of 
From the figure, it can be written
Considering horizontal motion
(c) The vertical velocity with which it strikes the ground is given by
Thus, the ball strikes with a vertical velocity of 
Speed of an object is kinetic energy
