The angle of the wedge is 30°.
Answer:
5.88 ft/s
Explanation:
a) The block will slide down due to it's weight.
initial velocity u= 0
final velocity, v
acceleration, a = g sin 30° = 32 ft/s²× sin 30° = 16 ft/s²
Sliding displacement, s = 3ft
Use third equation of motion:

substitute the values and solve for v

b) Use conservation of momentum:
Initial momentum of the system = 0
final momentum = (15) ( 9.8)+ (25)(v')
v' = 5.88 ft/s
Answer:
Explanation:
Cutting a string in half because
b is irreversible
c is a cheical and d is also a chemical change
Answer:
468 m
Explanation:
So the building and the point where the laser hit the water surface make a right triangle. Let's call this triangle ABC where A is at the base of the building, B is at the top of the building, and C is where the laser hits the water surface. Similarly, the submarine, the projected submarine on the surface and the point where the laser hit the surface makes a another right triangle CDE. Let D be the submarine and E is the other point.
The length CE is length AE - length AC = 284 - 234 = 50 m
We can calculate the angle ECD:


This is also the angle ACB, so we can find the length AB:



So the height of the building is 468m
Answer: A
Out of the screen
Explanation:
Using right hand rule, the magnetic force is perpendicular to the plane form by the magnetic field of a charged particle and its speed. Which will be into the screen.
But the negative charged particle moves in the opposite direction of the positive charged particle. Therefore, the magnetic force direction will be out of the screen