Answer:
a) u = 30.29 m/s
b) t = 2.09 s
Explanation:
given,
velocity = 45 m/s
angle (θ) = 50°
horizontal velocity = 45 cos 50°
time taken to reach 150 m.
times = 
t = 5.19 s
a) height of arrow



s = 46.78 m
v² - u² = 2 g s
u² = 2 × 9.81 × 46.78
u = 30.29 m/s
b) time taken by the apple = 
= 3.09 s
time after which it has to be thrown = 5.19-3.09 = 2.1 s
Answer:0.27
Explanation:
Given
One worker Pushes with force 
other Pulls it with a rope of rope 
mass of crate 
both forces are horizontal and crate slides with a constant speed
Both forces are in the same direction so Friction will oppose the forces and will be equal in magnitude of sum of two forces because crate is moving with constant speed i.e. net force is zero on it

where
is the friction force



where
is the coefficient of static friction



b. describes it best because a form of molten cools down and makes igneous rock. Good luck! Please mark me brainliest!
Answer:
Explanation:
N=Rotor Speed in Revolution per minute(rpm)
for P=4 and N=3600, f comes out to be 120 Hz.
So frequency of voltage produced is 120 Hz. But this is not practical. Generally 4-Pole generator has N=1500rpm(for 50 Hz) or 1800rpm for 60 Hz. Two pole generator can have N=3600rpm(f=60Hz).
The most practical situation is generator having N=3600Hz with 2 Poles.
Hope It will be helpful!!!
<h3><u>Answer;</u></h3>
Mechanical advantage
<h3><u>Explanation;</u></h3>
- Mechanical advantage is the ratio of force output from a machine divided by the force input into the machine.
- Mechanical advantage measures the machine's force-magnifying effect. It is an advantage gained by using simple machines to accomplish work with less effort.
- The formula is; M.A = output force/ Input force