Answer:
magnetic fields is stronger at the pulls because opposites attract which is why the pull is stronger.
this was written by me.
Explanation:
John can run with the velocity of 5 m/s
Explanation:
- Kinetic energy is defined as the energy is being used to do an activity, basically energy associated with the motion of objects in the universe.
- The formula used to find the kinetic energy of an object is k =
where as k represented as kinetic energy, m is the mass of the object and v is the velocity of the given object.
- Here, to find the answer we have to re-write the equation as
![v = \sqrt[2]{\frac{2 k}{m} }](https://tex.z-dn.net/?f=v%20%3D%20%5Csqrt%5B2%5D%7B%5Cfrac%7B2%20k%7D%7Bm%7D%20%7D)
- Given, the mass of the object, here it is John = 80 kg, energy needs to be converted to kinetic energy, k = 1000 J.
- Hence, substitute all the values, then you would velocity as 5 m/s
Answer: D. 0.29 m
Explanation:
We will use the following equations to describe the leap of the cat:
(1)
(2)
Where:
is the height of the cat
is the cat's initial velocity
is the acceleration due gravity
is the time
is the y-component of the velocity
Now the cat will have its maximum height 
when 
. So equation (2) is rewritten as:
(3)
Finding :
(4)
(5)
(6)
Substituting (6) in (1):
(7)
Finally:
(8)
The moon is thought to have an iron-rich core whose radius
is 330 km, plus or minus an uncertainty of 20 km.
That puts its diameter in the range of 620 km to 700 km.
Answer:
Concepts and Principles
1- Kinetic Energy: The kinetic energy of an object is:
K=1/2*m*v^2 (1)
where m is the object's mass and v is its speed relative to the chosen coordinate system.
2- Gravitational potential energy of a system consisting of Earth and any object is:
U_g = -Gm_E*m_o/r*E-o (2)
where m_E is the mass of Earth (5.97x 10^24 kg), m_o is the mass of the object, and G = 6.67 x 10^-11 N m^2/kg^2 is Newton's gravitational constant.
Solution
The argument:
My friend thinks that escape speed should be greater for more massive objects than for less massive objects because the gravitational pull on a more massive object is greater than the gravitational pull for a less massive object and therefore the more massive object needs more speed to escape this gravitational pull.
The counterargument:
We provide a mathematical counterargument. Consider a projectile of mass m, leaving the surface of a planet with escape speed v. The projectile has a kinetic energy K given by Equation (1):
K=1/2*m*v^2 (1)
and a gravitational potential energy Ug given by Equation (2):
Ug = -G*Mm/R
where M is the mass of the planet and R is its radius. When the projectile reaches infinity, it stops and thus has no kinetic energy. It also has no potential energy because an infinite separation between two bodies is our zero-potential-energy configuration. Therefore, its total energy at infinity is zero. Applying the principle of energy consersation, we see that the total energy at the planet's surface must also have been zero:
K+U=0
1/2*m*v^2 + (-G*Mm/R) = 0
1/2*m*v^2 = G*Mm/R
1/2*v^2 = G*M/R
solving for v we get
v = √2G*M/R
so we see v does not depend on the mass of the projectile
