Answer:
Deceleration
Explanation:
The amount by which a speed or velocity decreases
Answer:
Explanation:
Power P = V² / R
a ) The resistance is changed to 2.90R
Power will become 1 / 2.9 times .
b )The voltage of the battery is now 2.90V, but the resistance is R
P = (2.9V)² / R
= 8.41 x V² / R
So power becomes 8.41 times
c )The resistance is 2.90R and voltage is 2.90V
Power P = (2.9V)² / 2.9 R
= 2.9 V²/R
So power becomes 2.9 times
d ) The resistance is 2.90R and the voltage is V/2.90
Power P = ( V/2.90)² x 1 / 2.90R
1 / ( 2.9 )³ x V² / R
= 1 / 24.389 x V² / R
So power becomes 1 / 24.389 times .
The speed is changing its direction all the time. There
is an acceleration which changes the direction of the speed – that is called
centripetal acceleration. Only uniform linear motions are considered to have no
acceleration.
This is the general formula for acceleration
a = dv/dt
When calculating dv, you should keep in mind the change
in the velocity vector’s direction. You can easily see in a graph that with dt
tending to 0 (so the length of the arc covered is also tending to 0), the difference
between vectors Vf and V0 has a direction which is perpendicular to velocity
(the shorter the arc, the closest the angle is to 90 degrees).
There is a formula (which can be deducted from the
previous formula) which allows you to calculate the acceleration:
a = v^2/r
Let’s talk about the units:
v is in m/s
r is in m
so v^2/r
is in (m/s)^2/m = (m^2/s^2)/m = m/s^2
which is the same unit as dv/dt:
dv/dt = (m/s)/s= m/s^2
