Answer:
so initial speed of the rock is 30.32 m/s
correct answer is b. 30.3 m/s
Explanation:
given data
h = 15.0m
v = 25m/s
weight of the rock m = 3.00N
solution
we use here work-energy theorem that is express as here
work = change in the kinetic energy ..............................1
so it can be written as
work = force × distance ...................2
and
KE is express as
K.E = 0.5 × m × v²
and it can be written as
F × d = 0.5 × m × (vf)² - (vi)² ......................3
here
m is mass and vi and vf is initial and final velocity
F = mg = m (-9.8) , d = 15 m and v{f} = 25 m/s
so put value in equation 3 we get
m (-9.8) × 15 = 0.5 × m × (25)² - (vi)²
solve it we get
(vi)² = 919
vi = 30.32 m/s
so initial speed of the rock is 30.32 m/s
Answer:
200 m\ s Ans .....
Explanation:
Data:
f = 200 Hz
w = 1.0 m
v = ?
Formula:
v = f w
Solution:
v = ( 200)(1.0)
v = 200 m\s <em>A</em><em>n</em><em>s</em><em> </em><em>.</em><em>.</em><em>.</em><em>.</em><em>.</em><em>.</em><em>.</em><em>.</em><em>.</em>
Answer:
Explanation:
From the question we are told that:
Charges:
Distance 
Generally the equation for Force is mathematically given by
Therefore
You haven't told us the "wattage" rating of the bulb. We'll just have to call it ' W ' .
The bulb uses energy at the rate of W watts, or 0.001W kilowatts.
In 12 hours, it uses <em>0.012W kilowatt-hours </em>of energy.
= = = = =
W watts = W Joules/second
1 hour = 3600 seconds
12 hours = (12 x 3600) seconds
Energy = (W Joule/sec) x (12 x 3600 sec)
<em>Energy = 43,200W Joules</em>
