Kinetic energy = (1/2) (mass) (speed²).
A Physicist in the canoe, or on a raft floating downriver next to the canoe, will say that the canoe's kinetic energy is zero.
A Physicist on the riverbank, watching the canoe drift by at 1 m/s, will say that its kinetic energy is 9 Joules.
They're both correct.
If an object is thrown in an upward direction from the top of a building 1.60 x 102 ft. high at an initial velocity of 21.82 mi/h, what is its final velocity when it hits the ground? (Disregard wind resistance. Round answer to nearest whole number and do not reflect negative direction in your answer.)
this question is troubling me i guessed 96 ft/s
can someone help me out and explain it thanks so much!!!!!!
Answer: 2.55meter
Explanation: Using the second equation of motion.
S{hieght} = U*t + {g*t²}/2
Where U is initial velocity =0m/s
g is acceleration due to gravity 10m/s²
t is time 1secs
So we have,
hieght = 0 + {g*t²}/2
hieght = {10*(1)²}/2
Total hieght travelled is 10/2
Which is 5 meter.
But we are asked to find the hieght above the window which as a hieght of 2.45meter.
So,
hieght above window would be
{5 - 2.45}meter
Which is 2.55 meter.
<h2>
Answer: 745.59 nm</h2>
Explanation:
The diffraction angles 
when we have a slit divided into 
parts are obtained by the following equation:
(1)
Where:
is the width of the slit
is the wavelength of the light
is an integer different from zero
Now, the first-order diffraction angle is given when 
, hence equation (1) becomes:
(2)
We know:
In addition we are told the diffraction grating has 750 slits per mm, this means:
Solving (2) with the known values we will find :
(3)
(4)
Knowing 
:
>>>This is the wavelength of the light, wich corresponds to red.
