Ans: D
In a projectile motion, horizontal velocity is constant, while the ball is travelling at a constant vertical acceleration due to the gravity (9.81 ms-2 on Earth).
Answer:
98%
Explanation:
Given parameters
Mass of motor = 10kg
Height = 2m
Time = 2s
Power input = 100w
Unknown
Efficiency = ?
Solution
Efficiency is the percentage of the power output to the power input.
Power is the rate at which work is done.
Power output = mass x g x height / time
g is the acceleration due to gravity
Power output = 10x 2 x 9.8 / 2 = 98W
Efficiency = power output/ power input x 100
Efficiency = 98/100 x 100 = 98%
Answer:
The water level in the bath tub is rising at a rate of 0.0111 ft/s
Explanation:
Volume of the bath tub = (Area of base) × (height)
Area of base = 18 ft² (constant)
Height = h (variable)
V = 18h
(dV/dt) = 18 (dh/dt)
If (dV/dt) = 0.2 ft³/s
0.2 = 18 (dh/dt)
(dh/dt) = (0.2/18)
(dh/dt) = 0.0111 ft/s
Hope this Helps!!!
That's a great idea ! A wind turbine (windmill) or solar panels
on the roof of every WalMart, but don't stop there. Let K-Mart,
Target, Sears, Macy's, 7-11, McDonald's, and Subway in on it too.
In fact, why not place them on the roof of every house and
apartment building too ?
Just one question: Who's going to pay for them ?
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The biggest single year-round residential use of energy in the
USA is to heat up and keep a ready supply of hot water. So the
single biggest residential use of energy could be eliminated with
a simple solar water heater on the roof of every house. From my
own personal observation, I know that Israel is there now, but here
in the USA, it's apparently not worth the time, effort, or expense ! ? !
Answer:
v0 = 25 m/s
vf = 0 m/s
a = -9.80 m/s^2
change in x = 31.89m
but that's only 1/3 of the hight, so i time it by 3 to get 96m