Simply put, our solar system is a speck compared to the Milky Way. Our Milky Way galaxy is a whopping 587 trillion light-years across.
Answer:
F = −10093.41 N
Explanation:
Given that,
Mass of a baseball, m = 143 g = 0.143 kg
Initial speed of the baseball, u = +38.8 m/s
The hitter's bat is in contact with the ball for 1.20 ms and then travels straight back to the pitcher's mound at a speed of 45.9 m/s, v = -45.9 m/s
We need to find the average force exerted on the ball by the bat. So, Force is given by :
a is acceleration
So, the average force exerted on the ball by the bat has a magnitude of 10093.41 N.
Answer:
(a) F = 239.575 N (b) t = 0.00649s or 6.49 ms
Explanation:
(a) By law of energy conservation, the bullet kinetic energy will be transferred to work done on stopping it from moving.
Formula for Kinetic Energy where m is bullet mass, v is the velocity
Formula for work where F is the average force and S is the distance travelled.
Substitute m = 4.2 g = 0.0042 kg, v = 370 m/s and S = 1.2 (m)
(b) If the force is constant, since the mass is constant and F = ma according to Newton's 2nd law, the acceleration on bullet is also constant
We also have
At the time the bullet is coming to rest,
Therefore,
Answer:
Net external force acting on the rock when it is at the top of its trajectory is force due to gravity (mg).
Explanation:
The forces acting on a rock thrown up are force due to gravity and air resistance. Air resistance is directly proportional to velocity of rock, when velocity is zero air resistance is zero. When it is at the top of its trajectory its velocity is zero. So air resistance is also zero. Hence only gravitational force acts on the rock.
Net external force acting on the rock when it is at the top of its trajectory is force due to gravity (mg).
I believe it’s self-referent encoding