Speed is constant. 50 miles = 1 hour. 600/50 = 12. 1hr(12) = 12 hours.
The average velocity is -4.17 m/s
Explanation:
The average velocity of a body is given by:

where
d is the displacement of the body
t is the time elapsed
For the student in this problem, we have:
Initial position: 
Final position: 
So the displacement is

The time elapsed is
t = 60 s
Therefore, the average velocity is

Where the negative sign means the student is moving towards the origin.
Learn more about average speed and velocity:
brainly.com/question/8893949
brainly.com/question/5063905
#LearnwithBrainly
Answer:

Explanation:
The volume of the balloon can be find compared the force in each cases so:
reduce 25% from 74kg

So the net force uproad on the balloon is

Now the density of the both gases air and helium are different however the volume is the same change offcorss the mass so:






Answer:
The angle of banked curve that makes the reliance on friction unnecessary is

Explanation:
In order the car to stay on the curve without friction, the net force in the direction of radius should be equal or smaller than the centripetal force. Otherwise the car could slide off the curve.
The only force in the direction of radius is the sine component of the weight of the car

The cosine component is equivalent to the normal force, which we will not be using since friction is unnecessary.
Newton’s Second Law states that

Also, the car is making a circular motion:

Combining the equations:

Finally the angle is

Answer:
He can throw it away from himself.
Explanation:
Newtons Third Law says that everything has an equal, yet opposite reaction on other objects.