Acceleration = (change in speed) / (time for the change)
change in speed = (speed at the end) minus (speed at the beginning)
change in speed = (zero) minus (28 m/s) = -28 m/s
Acceleration = (-28 m/s) / (13 sec)
Acceleration = -2.15 m/s²
B. Energy
A power company charges its customers for electricity based upon B. Energy.
<h3>
Explanation:</h3>
Kilo-watt Hours (kWh) is the unit that measures the electricity consumption of customers. Since Power is defined as the rate at which electrical energy is transferred by an electrical circuit per unit time,

If energy is transmitted at a constant rate over a period of time, the total energy in kilowatt hours is the product of power in kilowatts(kW) and time in hours (h)

Answer: A (
,309.8°)
B (2
, 315°)
C (
, 26.56°)
Explanation: To transform rectangular coordinates into polar coordinates use:
and 
For point A:




°
Point A is in the II quadrant, so we substract the angle for 360° since it is in degrees:

309.8°
Polar coordinates for point A is (
, 309.8°)
For point B:





°
Point B is in IV quadrant, so:

315°
Polar coordinates for point B is (
, 315°)
For point C:





26.56°
Polar coordinates for point C is (
, 26.56°)
Answer:
A lone neutron spontaneously decays into a proton plus an electron.
Explanation:
In an atom, nuclei contain protons and neutrons, which are the fundamental particles of an atom. Neutrons are stable and uncharged particles inside a nucleus.
For 15 times during its lifetime, a free neutron decays and breaks down into more smaller particles.This breakdown causes problems in nuclear reactors, as they start decaying and emit radiations of different wavelengths.
A neutron undergoes the decaying process to produce an electron, a proton, and energy.
The reaction of neutron decay:
n0 → p+ + e− + νe
Using conservation of energy law:-
∑ work in = ∑ work out
and work= force* displacement
so when we wanted to move a 100kg a distance of 1m
we multiplied 100*1 = work out
so work in should be equal to 100*g Joules, where g is the acceleration due to gravity.
so workout = 100*g = 25*g *x (divide both sides by 25*g)
x=4m
by the same way:-
------------------------
work in = 100kg * 2m * g (m/

)= work out
so work out = 25*x*g = 200* g (divide both sides by 25*g)
x=8m