Explanation:
We have,
Mass of an automobile is 1150 kg
The automobile traveling at 86 km/h and then it comes to stop.
86 km/h = 23.88 m/s
It is required to find work done by the automobile.
Concept used : Work energy theorem
Th change in kinetic energy of an object is equal to the work done by it. The work done is then given by :
Here, v = 0
or
Therefore, the work done by the automobile is .
Answer:Theoretical Discussion
The diffraction of classical waves refers to the phenomenon wherein the waves encounter an obstacle that fragments the wave into components that interfere with one another. Interference simply means that the wave fronts add together to make a new wave which can be significantly different than the original wave. For example, a pair of sine waves having the same amplitude, but being 180◦ out of phase will sum to zero, since everywhere one is positive, the other is negative by an equal amount.
Answer: Negative acceleration
Explanation:
According to the described situation we have two velocities:
-An initial velocity during the first hour:
-A final velocity during the last 200 miles:
As we can see, the final velocity is less than the initial velocity, this means the plane's velocity decreased.
On the other hand, acceleration is defined as <u>the variation of velocity in time:</u>
Since the plane's velocity decreases, the acceleration is negative.
Hence, this situation is an example of negative acceleration.
Answer:
C) they all have the same angular speed
D) they all have the same angular acceleration
Explanation:
Wrong --> they all have the same tangential speed. The points close to the axis will have less speed than the points away from the axis.
Wrong --> they all have the same tangential acceleration. Similarly, the points close to the axis will have smaller acceleration than the points away from the axis.
Correct --> they all have the same angular speed. Angular speed is the same for all the particles in the rotating object.
Correct --> they all have the same angular acceleration. Angular acceleration is the same for all the particles in the rotating object.
This all comes from the following relations:
v = ωR
a = αR
where ω is the angular velocity and α is the angular acceleration.
As can be seen from above, tangential velocity and acceleration depends on the distance from the axis, whereas the angular velocity and acceleration is the same for all the points on the rotating body.
Answer:
t=1s
Explanation:
Using the formula
s=ut+1/2at^2
4.9 = (0)(t) + 1/2(9.8)(t^2)
4.9 = 4.9(t^2)
t^2 = 1
t = 1