Answer:
the required height is 0.2449 m only
Explanation:
Given the data in the question;
Initial height = 2m
so speed of the puck before hitting the ground will be;
u² = 2gh
Initial speed u_ball = √2gh
u_ball = √( 2 × 9.8 × 2 )
u_ball = √39.2
u_ball = 6.26 m/s
given that; FOR THE FROZEN PUCK, coefficient of restitution = 0.35 only
R = - (v_ball - v_ground / u_ball - u_ ground)
so
0.35 = - (v_ball - 0 / 6.26 - 0)
0.35 = -v_ball / - 6.26
-v_ball = 0.35 × (- 6.26)
-v_ball = -2.191 m/s
v_ball = 2.191 m/s
to get the height;
v² = 2gh
h = v² / 2g
we substitute
h = (2.191)² / 2×9.8
h = 4.800481 / 19.6
h = 0.2449 m
Therefore, the required height is 0.2449 m only
Answer:
6.2 ohm
Explanation:
Let R1 = 5 ohm
R2= 3 ohm
R3= 2 ohm
Since R3 and R2 are parallel then net resistance R' is given by
1/R' = 1/R2 + 1/R3
1/R' = 1/3 + 1/2
1/R' = 5/6
then
R' = 6/5 = 1.2 ohm
Now R1 and R' are in series, so
R = R1 + R'
R = 5 + 1.2
R = 6.2 ohm
Because rockets do accelerate in space and have been able to do so for a long time.
Answer: Option D
<u>Explanation:</u>
A rocket is made to reach the sky and its required destination by the burning of fuels in the rocket. So there is no need of any other external forces to propel them in space. As per Newton's third law, the action and reaction forces will help the rockets to escape the orbit of earth.
And then the remaining energy required by the rocket to travel in space will be obtained from the burning of fuels in the compartments. This burning of fuels in respective compartments will propel the rockets in space. So it is a complete myth that space travel was impossible before because of inability to provide propulsion in space.
Answer:
The temperature rise of the water is = 0.14 °c
Explanation:
Height = 60 m
Potential energy change ΔP = 
ΔP = m × 9.81 × 60
ΔP = (588.6 × m) Joule
Since the Potential energy change is equal to the internal energy change or Enthalpy change.
ΔP = ΔH
Since ΔH = m × C × ΔT
⇒ ΔP = m × C × ΔT
Put all the values in above formula we get
⇒ 588.6 × m = m × 4184 × ΔT
⇒ ΔT= 0.14 °c
Therefore the temperature rise of the water is = 0.14 °c
Answer:
abcdefghijklmnopqrstuvwxyz