Answer:
2.35 seconds
Explanation:
Remark
This is a question where direction matters. Let us call down + and up minus. It won't matter. The answer will be the same.
Formula
a = (vf - vi)/t
Givens
a = 9.8 m/s^2
vi = - 15 m/s
vf = 8m/s
Solution
9.8 = (8 - - 15)/t Multiply both sides by t
t * 9.8 = 23 Divide by 9.8
t = 23/9.8
t = 2.35 s
Answer:
Explanation:
1) Make sure the service portion of the structure stays above the highest probable water level.
2) Make sure the support structure in contact with the water can withstand the tidal flows
3) Consider whether the added restriction of the proposed structure will altar the height of, or water velocity contained in, the tidal exchanges.
4) Consider whether a dock needs to have mechanisms to compensate for large sea level changes.
<span>Don't know what you mean by Earths Spheres. The Earth is a sphere -- singular. And it is made up of LOTS of matter</span>
Answer:
q2 = 5.1μC
Explanation:
From a forces diagram we can stablish that:
Fe = T*sin(16) (eq1)
T*cos(16) = m*g (eq2)
Where Fe is the electric force and T is the tension of the string. Solving for Fe:
Fe = m*g*tan(16)
The magnitude of the electric force is calculated as:
Solving for q2:
Answer:
Explanation:
Maximum force for forehead = 6 kN
maximum force for cheek bone = 1.3 kN
Part A:
mass of base ball, m = 140 g = 0.14 kg
initial velocity of base ball, u = 30 m/s
final velocity of base ball, v = 0
Time, t = 0.0015 s
Acceleration is defined a the rate of change of velocity.
Use first equation of motion
v = u + at
0 = 30 + a x 0.0015
a = - 20000 m/s²
Part B:
Force = mass x acceleration
F = 0.140 x 20000
F = 2800 N
Part C:
Force applied on your head is 2800 N.
Part D:
As the force is 2800 N that means 2.8 kN which is less than 6 kN so you are safe.
