Answer: -7J
Explanation:
To determine the change in potential energy, use the equation ΔPE=mgΔh
Δ
PE=mg
Δ
h
, where m is the mass, g= 9.8 m/s2
g= 9.8 m/s
2
, and Δh is the change in height. Hence, we have that the potential energy PE=4.0 kg×9.8 m/s2×-2.0 m=-78 J
PE=4.0 kg
×
9.8 m/s
2
×
-2.0 m=-78 J
. To verify that this is correct, note that since the cat changes the potential energy to kinetic energy by jumping, the potential energy decreases. Hence, the potential energy should be negative.
Answer:
Explanation:
Given that,
Charge, 
Revolution = 7 rev
magnetic field, B = 45 mT
Time, t = 1.29 ms
We need to find the mass of the ion. Let m be the mass. The formula for the mass in terms of time period is given by :
So, the mass of the ion is equal to 
.
Answer:
Explanation:
This is a simple Law of Momentum Conservation problem of the inelastic type. The equation for this is
![[m_1v_1+m_2v_2]_b=[(m_1+m_2)v]_a](https://tex.z-dn.net/?f=%5Bm_1v_1%2Bm_2v_2%5D_b%3D%5B%28m_1%2Bm_2%29v%5D_a)
Filling in:
![[1200(4.5)+2100(0)]=[(1200+2100)v]](https://tex.z-dn.net/?f=%5B1200%284.5%29%2B2100%280%29%5D%3D%5B%281200%2B2100%29v%5D)
which simplifies to
5400 + 0 = 3300v
so v = 1.6 m/s to the east, choice B
Answer:
Quick maths
First you find the fafarick and the lalickc and the caprisum and the joinnt
Answer:
Rutherford bombarded aluminum foil with beam of light known as alpha particles. The mass of this alpha particle is equivalent to helium atom.
Explanation:
Rutherford bombarded aluminum foil with beam of light known as alpha particles. The mass of this alpha particle is equivalent to helium atom.
When this alpha particles were made to strike the aluminum foil, some passed through the foil, some were reflected and speed others changed.
The ones reflected encountered heavier particle known as the nucleus, preventing them from passing through it. The whole observations indicated that atom is not is uniformly charged sphere as proposed by J.J Thomson.
Rutherford proposed new model known as the Planetary model of atom, which described atom as containing a nucleus which is revolved by electron, just like planets revolve round the sun. And this nucleus contains opposite charge to electron which is proton, to balance the motion.
