Answer:
A. Acceleration always involves changing speed.
Explanation:
Acceleration is defined as the rate of change of velocity.
Velocity is a vector quantity and is defined as speed in a given direction. Therefore, when any or both of the components of velocity is changing with time, a body is said to be accelerating i.e. acceleration involves a change of speed or change in direction, or a change in both speed and direction.
Considering the statements:
A. Acceleration always involves changing speed is false because acceleration can occur when speed is constant but direction is changing.
B. Changing direction always involves acceleration is true because, a change in direction results in a change in velocity.
C Changing speed always involves acceleration is true because, changing speed results in a change in velocity.
D. Circular motion always involves acceleration is true because in circular motion the direction is always changing, and this results in a change in velocity
image distance,di=10 cm
object distance,do=20cm
magnification, m=di/do
=10/20
=0.5
since the image is virtual, magnification is negative.
therefore m=-0.5
Answer:
a)40100m/s
b)-4.348x10^- m/s^2
Explanation:
to calculate the change in the planet's velocity we have to rest the speeds
ΔV=-22.8-17.3=-40.1km/s=40100m/s
A body that moves with constant acceleration means that it moves in "a uniformly accelerated movement", which means that if the velocity is plotted with respect to time we will find a line and its slope will be the value of the acceleration, it determines how much it changes the speed with respect to time.
When performing a mathematical demonstration, it is found that the equations that define this movement are as follows.
Vf=Vo+a.t (1)\\\\
{Vf^{2}-Vo^2}/{2.a} =X(2)\\\\
X=Xo+ VoT+0.5at^{2} (3)\\
Where
Vf = final speed
Vo = Initial speed
T = time
A = acceleration
X = displacement
In conclusion to solve any problem related to a body that moves with constant acceleration we use the 3 above equations and use algebra to solve
for this problem we have to convert the time interval ins seconds, we know that a year has 53926560s
t=1.71years=53926560*1.71=92214417.6
then we can use the ecuation number 1 to calculate the aceleration
Vf=-22.8km/s
Vo=17.3km/s
Vf=Vo+at
a=(vf-vo)/t
a=(-22.8-17.3)/92214417.6
a=-4.348x10^-7 km/s^2=-4.348x10^- m/s^2
A blackbody curve represents the relation between <u>intensity of radiation with wavelength.</u>
Here in this curve we can see that all ideal blackbody radiates almost all wavelength of radiations and these radiations are of different intensity.
here intensity will be maximum for a given wavelength of radiation and the relation of this wavelength with the temperature of the object is given by Wein's law
It is given by
now if we increase the temperature the maximum intensity for which wavelength is given will shift to the left.
Using this all we can also compare the temperature of two blackbody for which radiation graph is given to us.
The answer would be B because humans cannot see electrons so we visualize the electrons due to the theory