240 = 0+1/2 (-9.8t
240 = -4.9t
<span>240/-4.9 = t</span><span>
</span>49.0 = t
t= 7.0s
Hi!
SI units are physical measurements which will be in the form of kilograms, second, kelvin, metres, etc.
Since kilograms measure the weight of an object, it is out. Miles and feet are not SI units, so they are also out. This only leaves one answer left!
Hopefully, this helps! =)
T = 3.5 secs
Velocity (v) = g * t = 10 m/s^2 * 3.5 sec = 35 m/s
a) At a position of 2.0m, the Initial energy is
all made up of the potential energy=m*g*hi<span>
and meanwhile at 1.5 all its energy is also potential energy=m*g*hf
The percentage of energy remaining is E=m*g*hi/m*g*hf x 100
and since mass and gravity are constant so it leaves us with
just E=hi/hf
which 1.5/2.0 x100= 75% so we see that we lost 25% of the
energy or 0.25 in fraction
b) Here use the equation vf^2=vi^2+2gd
<span>where g is gravity, vf is the final velocity and vi is the
initial velocity while d is the distance travelled
so in here we are looking for the vi so let us isolate that
variable
we know that at maximum height or peak, the velocity is 0 so
vf is 0
therefore,</span></span>
vi =sqrt(-2gd) <span>
vi =sqrt(-2x-9.81x1.5) </span>
<span>vi =5.4 m/s
<span>c) The energy was converted to heat due to friction with the
air and the ground.</span></span>
They typically represents different wavelengths of element due to its energy emission in the form of visible light. When an electron of that particular element move from a higher energy level down to a lower energy level, it gives off energy in the form of photon emission. Atom of a certain element has a unique electron arrangement thus it can considered that particular element's spectrum is unique.
