Assuming negligible air resistance, the shell travels at a constant horizontal velocity equal to what it had immediately after leaving the barrel. The shell is in the air until hitting the target; the length of this period of time is therefore directly proportional to the distance between the barrel and the target.
The shell hits the target below where it was aimed at for it experiences gravitational pull during its flight. With the barrel pointed "parallel to the ground" the shell shall experience no initial vertical velocity, meaning that it its undergoing a freefall on the vertical direction. and are therefore the respective vertical displacements of the two trials.
The formula below relates the vertical displacement to the gravitational acceleration and the time duration of the freefall :
Let and be the duration of the shell's flight on the first and second trials, respectively; Thus
Explanation:
It is given that,
Total mass is 70 kg
The truck exerts a constant force of 20 N.
Then the net force is given by :
F = ma
a is acceleration of rider
Initial velocity of rider is 0. So, using equation of kinematics to find the final velocity as :
Since, 1 m/s = 2.23 mph
4.28 m/s = 9.57 mph
So, the speed of the rider is 4.28 m/s or 9.57 mph.
Answer:
45 m
Explanation:
From the question given above, the following data were obtained:
Mass (m) = 0.5 kg
Initial height (h₁) = 30 m
Initial potential energy (PE₁) = 20 J
Final potential energy (PE₂) = 30 J
Final height (h₂) =?
From:
PE = mgh
PE / h = mg = constant
Thus,
PE₁ / h₁ = PE₂ / h₂
With the above formula, we can obtain the final height of the bird as follow:
Initial height (h₁) = 30 m
Initial potential energy (PE₁) = 20 J
Final potential energy (PE₂) = 30 J
Final height (h₂) =?
PE₁ / h₁ = PE₂ / h₂
20 / 30 = 30 / h₂
Cross multiply
20 × h₂ = 30 × 30
20 × h₂ = 900
Divide both side by 20
h₂ = 900 / 20
h₂ = 45 m
Therefore, the final height of the bird is 45 m.
Solar energy ....................
Answer:
The overall sky a Bellingham observer would see is about 75-100% over the period of 1 year.
Explanation:
Due to following factors, the overall sky visibility will fall in this range.
- The location of Bellingham on Earth is in the Northern hemisphere over the equator.
- The tilt of the earth cannot allow the visibility of the complete sky.
- The light pollution and aerosol concentrations has reduced the sky visibility at night.