Answer: 
Explanation:
Given : The escape velocity : 
We know that 1 mile = 1609 meters (approx)
and 1 hour= 3600 seconds
To convert escape velocity 2.5 x 10 miles per hour into m/s , we need to multiply it by 1609.34 and divide it by 3600.
Thus, the escape velocity in m/s is given by :-

Hence, the speed in m/s = 11.17
6.
Basically, all of these questions use F = ma
m = 80 kg
a = 1.62
Weight = F = 80*1.62 = 129.6
The closest answer is B
7.
<em><u>Step One</u></em>
Find the mass here on earth
m = F/a
F = 40 kg
a = 9.2
F = 40/9.2 = 4.34
Now take everything to the moon
F = 20 kg
a = ??
m = 4.34
a = F/m = 20/4.34 = 4.6 m/s^2
8
m = 40 kg
F = 20 N
a = ??
a = F/m = 20N/40kg = 1/2 m/s^2
Comment
All of these depend on F = m*a. None but the first one talk about vertical forces where gravity would play a part. Moving horizontally means that there is no gravitational force if there is no friction. a = 9.8 has nothing to do with the problem.
Answer:
84.6 J
Explanation:
The work done by the force is given by

where
W is the work done
F = 15 N is the force applied
d = 6.0 m is the displacement
is the angle between the force's direction and the displacement
Substituting the numbers into the equation, we find

Answer:
The correct answer is d. tension pneumothorax.
Explanation:
The increasing build-up of air that is in the pleural space is what we call the tension pneumothorax and this happens due to the lung laceration that lets the air to flee inside the pleural space but it does not return.
Answer:
(a)

(b)
1120 N
Explanation:
Change in velocity,
is given by subtracting the initial velocity from the final velocity and expressed as 
Where v represent the velocity and subscripts f and i represent final and initial respectively. Since the ball finally comes to rest, its final velocity is zero. Substituting 0 for final velocity and the given figure of 8 m/s for initial velocity then the change in velocity is given by

To find
then we substitute 7 kg for m and -8 m/s for
therefore 
(b)
The impact force, F is given as the product of mass and acceleration. Here, acceleration is given by dividing the change in velocity by time ie

Substituting t with 0.05 s then 
Since F=ma then substituting m with 7 Kg we get that F=7*-160=-1120 N
Therefore, the impact force is equivalent to 1120 N