Answer:
-0.7 m/s
Explanation:
Initial velocity (u)= 2.5 m/s
Acceleleration (a)= -0.8 m/s^2
Time taken (t) = 4 seconds
Hence,
v=u+at [1st Equation of motion]
v=2.5+-0.8*4
v=2.5-3.2
v=-0.7 m/s
Note that the negative sign indicates that the ball has changed direction and rolls downwards with gravity
a)5m/s b)5
the 5 is because you add the seconds to get 8 seconds and then do the same with the distance to get 40. 40/8 = 5. speed = 5
Velocity = displacement/change in time
V = 40/8
I just realized how unorganised my math looks but I hope this is helpfull
<u>Solu</u><u>tion</u><u> </u><u>:</u><u>-</u>
Given that ,
- Initial Velocity of car = 44km / hr.
- Final Velocity of car = 0km / hr.
- Acceleration = -5km/hr².
To Find :
- Time taken to stop the car .
So , here use first equⁿ of motion which is ,

where ,
- v is final Velocity.
- u is Initial velocity.
- a is acceleration.
- t is time taken.
Now , substituting the respective values ,






Answer:
The efficiency of a Stirling engine is 74%
Explanation:
Given:
Temperature of gas when it is cold
K
Temperature of gas when it is hot
K
The efficiency of a stirling engine,




∴ 
Therefore, the efficiency of a Stirling engine is 74%