If the kinetic energy of each ball is equal to that of the other,
then
(1/2) (mass of ppb) (speed of ppb)² = (1/2) (mass of gb) (speed of gb)²
Multiply each side by 2:
(mass of ppb) (speed of ppb)² = (mass of gb) (speed of gb)²
Divide each side by (mass of gb) and by (speed of ppb)² :
(mass of ppb)/(mass of gb) = (speed of gb)²/(speed of ppb)²
Take square root of each side:
√ (ratio of their masses) = ( 1 / ratio of their speeds)²
By trying to do this perfectly rigorously and elegantly, I'm also
using up a lot of space and guaranteeing that nobody will be
able to follow what I have written. Let's just come in from the
cold, and say it the clear, easy way:
If their kinetic energies are equal, then the product of each
mass and its speed² must be the same number.
If one ball has less mass than the other one, then the speed²
of the lighter one must be greater than the speed² of the heavier
one, in order to keep the products equal.
The pingpong ball is moving faster than the golf ball.
The directions of their motions are irrelevant.
Answer:
Explained below
Explanation:
A) Newton's first law of motion states that an object will remain at rest or continue in its current state of motion except it is acted upon by another force.
Now using this law, when you jump off the ground, the earth will move a tiny bit and accelerate due to the force applied by the jumping.
B) Newton's 2nd law states that the acceleration of a system is directly proportional to the net external force acting on that system, is in the same direction with it and also inversely proportional to the mass.
In this case, when one jumps, an external force is exerted on the earth and we are told it is directly proportional to the acceleration of the system which in this case it's the earth, then it means that there is some motion by the earth even though you didn't see it move.
C) Newton's third law of motion states that to every action, there is an equal and opposite reaction.
In this case the motion of the jumper will lead to an equal and opposite reaction of the earth.
Answer:
Explanation:
We shall apply conservation of mechanical energy
kinetic energy of alpha particle is converted into electric potential energy.
1/2 mv² = k q₁q₂/d , d is closest distance
d = 2kq₁q₂ / mv²
= 2 x 9 x 10⁹ x 79e x 2e / 4mv²
= 1422 x2x (1.6 x 10⁻¹⁹)² x 10⁹ /4x 1.67 x 10⁻²⁷ x (1.5 x 10⁷)²
= 3640.32 x 10⁻²⁹ /2x 3.7575 x 10⁻¹³
= 484.4 x 10⁻¹⁶
=48.4 x 10⁻¹⁵ m
Answer:
t = 4.21x10⁻⁷ s
Explanation:
The time (t) can be found using the angular velocity (ω):
<em>Where θ: is the angular displacement = π (since it moves halfway through a complete circle)</em>
We have:
<u>Where</u>:
<em>v: is the tangential speed </em>
<em>r: is the radius</em>
The radius can be found equaling the magnetic force with the centripetal force:
Where:
m: is the mass of the alpha particle = 6.64x10⁻²⁷ kg
q: is the charge of the alpha particle = 2*p (proton) = 2*1.6x10⁻¹⁹C
B: is the magnetic field = 0.155 T
Hence, the time is:
Therefore, the time that takes for an alpha particle to move halfway through a complete circle is 4.21x10⁻⁷ s.
I hope it helps you!
Newton's Second law of motion:
Force = (mass) x (acceleration)
Force = (15kg) x (8m/s²) = 120 kg-m/s² = 120 newtons
