Answer:
The car strikes the tree with a final speed of 4.165 m/s
The acceleration need to be of -5.19 m/seg2 to avoid collision by 0.5m
Explanation:
First we need to calculate the initial speed
Once we have the initial speed, we can isolate the final speed from following equation:
Then we can calculate the aceleration where the car stops 0.5 m before striking the tree.
To do that, we replace 62 m in the first formula, as follows:
Answer:
1.37 rad/s
Explanation:
Given:
Total length of the tape is, m
Total time of run is, hours
We know, 1 hour = 3600 s
So, 2.1 hours = 2.1 × 3600 = 7560 s
So, total time of run is, s
Inner radius is,
Outer radius is,
Now, linear speed of the tape is,
Let the same angular speed be .
Now, average radius of the reel is given as the sum of the two radii divided by 2.
So, average radius is,
Now, common angular speed is given as the ratio of linear speed and average radius of the tape. So,
Therefore, the common angular speed of the reels is 1.37 rad/s.