<span>
The equation is h(t) = at^2 + vt + d
where a = acceleration of gravity = - 32.174 ft/sec^2
v = 25 feet/sec
d = starting height = 0
and h(t) = 0 when the ball hits the ground.
So, 0 = - 32.174t^2 + 25t + 0
You can use the quadratic formula on that if you want, or you can solve like this:
0 = - 32.174t^2 + 25t
0 = t ( -32.174t + 25)
So, one solution of that is t = 0, corresponding to the initial time when the ball is kicked.
The other time is: 25 = 32.174t
t = 25/32.174 = 0.777 seconds
or approximately 0.8 seconds.</span>
There are tons of forces that balance out on your body while you walk. Subsequent physics classes will tell you about each and how they are represented. Here are a few in order of how people usually learn them.
Gravity: The earth exerts a gravitational force on each particle in your body that has mass. Overall, this can be represented as a single force that pulls directly toward the center of the earth from the point called your center of mass.
Normal Force: The contact between your feet/shoes and the ground exerts a force normal (straight out from) the ground. If you are on flat ground, this force is directly opposite the force of gravity, and in most cases will be equal to it such that you have no vertical net force.
Friction: Friction between your shoes/feet and the ground, pointing parallel to the ground and in the direction of your walking motion creates the force necessary for you to move. The microscopic peaks and valleys of the ground and your feet/shoes create small normal forces that can sum into a direction of motion.
Air Buoyancy: Since you are in a fluid, the mass of the fluid you displace creates an upward force away from the center of the earth. Since the density of air is miniscule, this force is generally neglected except in the most precise of circumstances.
Drag and Air resistance: While you walk, as you move through a fluid, that fluid exerts friction on your body in the form of drag. It is usually small unless you’re moving very fast relative to the fluid.
Air pressure, blood pressure, body tensions: Your body has a balance of blood pressure, muscle tensions, which oppose outside air pressures which equalize out to form the shape your body is in.
Internal forces: Many forces act within you such as air pressure, other muscle tensions, and internal stresses which balance out. Usually in physics these are lumped under internal forces.
Answer:
Total strain when the stress was equal to 210 MPa = 0.101
Explanation:
See attached pictures.
Answer:
563.86 N
Explanation:
We know the buoyant force F = weight of air displaced by the balloon.
F = ρgV where ρ = density of air = 1.29 kg/m³, g = acceleration due to gravity = 9.8 m/s² and V = volume of balloon = 4πr/3 (since it is a sphere) where r = radius of balloon = 2.20 m
So, F = ρgV = ρg4πr³/3
substituting the values of the variables into the equation, we have
F = 1.29 kg/m³ × 9.8 m/s² × 4π × (2.20 m)³/3
= 1691.58 N/3
= 563.86 N
Answer:
velocity of the object
Explanation:
For an object moving at a constant acceleration, we would expect to see a position graph with a curved shape and a velocity graph with a straight shape.
