Answer:
v = dr/dt = 7t x + 0 y + (- 4) z
a = dv/dt = 7 x + 0 y + 0 z
t = 0:
v = (-4) z
a = 7 x
Explanation:
v = dr/dt = 7t x + 0 y + (- 4) z
a = dv/dt = 7 x + 0 y + 0 z
t = 0:
v = (-4) z
a = 7 x
Answer:
The total work on the ball is 36.25 Joules
Explanation:
There is an important principle on classical mechanics that is the work-energy principle it states that the total work on an object is equal the change on its kinetic energy, mathematically expressed as:
(1)
With W net the total work, Kf the final kinetic energy and Ki the initial kinetic energy. We're going to use this principle to calculate the total work on the baseball by the force exerted by the bat.
Kinetic energy is the energy related with the movement of an object and every classical object with velocity has some kinetic energy, it is defined as:

With m the mass of the object and v its velocity, knowing this we can use on:
In our case vf is the velocity just after the hit and vi the velocity just before the hit. For an average baseball its mass is 145g that is 0.145 kg, then

According to newton's third law: every action has an equal and opposite reaction, so yes the ground does move backwards. You have 4 forces acting on you at any given time: pushing force, friction force, gravity, and normal force. you push against something to propel forward, you have to overcome gravity and friction, and normal force keeps things upright to prevent them from falling into each other.
<span>If everything is motionless at every instant, and time is entirely composed of instants, then motion is impossible, so it must be an illusion.
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if you really want things to get confusing you can read up on zeno's dichotomy paradox stating that there is infinate amount of times you can divide something such as a distance traveled over time and you will stil
Average speed = (total distance covered) / (time to cover the distance)
-- Traveling at 40 mph for 1 hour, the distance covered is 40 miles.
-- Traveling at 60 mph for 1 hour, the distance covered is 60 miles.
-- Total distance covered = (40 miles) + (60 miles) = 100 miles
-- Total time = (1 hour) + (1 hour) = 2 hours
-- Average speed = (100 miles) / (2 hours)
<em>Average speed = 50 miles per hour</em>
Answer: Yes.
Explanation:
There is gravity in water because How does the water go up in the cycle? the garavity with the wind pull it up.