Answer:
Explanation:
a= 7.8i + 6.6j - 7.1k
b= -2.9 i+ 7.4 j+ 3.9k , and
c = 7.6i + 8.8j + 2.2k
r = a - b +c
=7.8i + 6.6j - 7.1k - ( -2.9i + 7.4j+ 3.9k )+ ( 7.6i + 8.8j + 2.2k)
= 7.8i + 6.6j - 7.1k +2.9i - 7.4j- 3.9k )+ 7.6i + 8.8j + 2.2k
= 18.3 i +18.3 j - k
the angle between r and the positive z axis.
cosθ = 18.3 / √18.3² +18.3² +1
the angle between r and the positive z axis.
= 18.3 / 25.75
cos θ= .71
45 degree
When light is reflected by a mirror, the angle of incidence is always <span>A. equal to the angle of reflection. We know this by the Law of Reflection.</span>
The best and most correct answer among the choices provided by your question is the third choice or letter C.
<span>The statement "Your hypothesis must be testable." is true about the scientific process.
</span>I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!
The Belt A has an efficiency of 50% while the Belt B has an efficiency of 25%
Why?
To calculate the efficiency of the belts, we need to consider that both conveyor belts are identical looking and both weights are equal (10 Newtons).
We need to remember that the formula to calculate work is equal to:
Also,
We know the following:
For belt A,
For belt B,
Now, to calculate the efficiencty of the belts, we can use the following formula:
We know that for both belts, the starting work was 20 J.
So, calculating we have:
Hence, we can see that The Belt A has an efficiency of 50% while The Belt B has an efficiency of 25%
Have a nice day!
