Answer:
Since it is falling freely, the only force on it is its weight, w.
w = m × g = 250 kg × 9.8 m/s^2 = 2450 Newton/N
Answer:443.1 s
Explanation:
Given
Engine of a locomotive exerts a force of 
Mass of train
Final speed (v)
F=ma
so 
and acceleration is
The speed of sound at T=25°C is Vs=346 m/s. So the sound has to reach the cliff and return back to you so the path it needs to travel is s=2*440 m = 880 m.
Since the speed of sound is constant s=Vs*t, and t= s/Vs=880/346=2.54335 s. You will hear the echo after t=2.54335 s after you shouted.
Answer:
The velocity is 40 ft/sec.
Explanation:
Given that,
Force = 3200 lb
Angle = 30°
Speed = 64 ft/s
The resistive force with magnitude proportional to the square of the speed,
Where, k = 1 lb s²/ft²
We need to calculate the velocity
Using balance equation
Put the value into the formula
Put the value of k
At terminal velocity 
So, 
Hence, The velocity is 40 ft/sec.
3. Millions of years ago, the Earth was not divided into 7 continents. It was only a very large land mass, the scientists named that one land mass “Pangaea”
4. If the tectonic plates are disturbed, they can cause mass earthquakes and tsunamis.
5. The ring of fire is a massive collection of volcanoes under the pacific ocean. They all form the shape of a ring, hence the name.
SORRY, I COULDNT ANSWER THE FIRST TWO QUESTIONS.
