Answer:
B) 1.2 N, toward the center of the circle
Explanation:
The circumference of the circle is:
C = 2πr
C = 2π (0.70 m)
C = 4.40 m
So the velocity of the ball is:
v = C/t
v = 4.40 m / 0.60 s
v = 7.33 m/s
Sum of the forces in the radial direction:
∑F = ma
T = m v² / r
T = (0.015 kg) (7.33 m/s)² / (0.70 m)
T = 1.2 N
The tension force is 1.2 N towards the center of the circle.
1. Proton
2. negative ion
3. electric charge
4. electron
5. repel
6. attract
7. positive ion
<span>rusting takes a long time, and rusting is a chemical change</span>
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.
They lack a cell nucleus.
