Answer:
86.6 lbs
Explanation:
Let the force is X.
Resultant force, R = 100 lbs
Other force is Y. Angle between resultant force and force X is 30°.
According to the diagram


X = 86.6 lbs
Other force Y


Y = 50 lbs
Answer
given,
vertical speed of stone,v = 12 m/s
height of the cliff = 70 m
a) time taken by the stone to reach at the bottom of the cliff
We know that,
S = u t + 1/2 a t²
- 70 = 12 t - 0.5 x 9.8 t²
4.9 t² - 12 t - 70 = 0
solving the equation
t = 5.2 s (neglecting the negative value)
b) again using equation of motion
v = u + a t
v = 12 - 9.8 x 5.2
v = -38.96 m/s
ignoring the negative sign
magnitude of velocity is equal to 38.96 m/s
c) total distance travel by the stone
vertical distance covered by the stone
v² = u² + 2 g h
0 = 12² - 2 x 9.8 x h
h = 7.34 m
to reach the stone to the same level distance travel be doubled.
Total distance travel by the stone
H = h + h + 70
H = 7.34 x 2 + 70
H = 84.7 m.
Hello,
I think that A is the right one.
Explanation:
both are different types of energy. one is elastic p.e while the other one is made by change in sound waves
Answer:
Calories, however you might want to back up my answer. I havent studied this topic in a while.