Answer:
Bottom left corner for whatever group that is
Lithium, sodium, and potassium all react with water
If the comb and the paper are attracted to each other the charge on the paper, is D)must be positive
<h3>
Laws of electrical attraction</h3>
This states that
- Like charges attract
- Unlike charges repel
Now, given that a negatively charged plastic comb is brought close to, but does not touch, a small piece of paper. If the comb and the paper are attracted to each other the charge on the paper, this implies that both the negatively charged plastic comb and the paper have opposite charges.
Since the charge on the plastic comb is negative, this means that the charge on the paper must be positive
So, if the comb and the paper are attracted to each other the charge on the paper, is D)must be positive
Learn more about electric charge here:
brainly.com/question/2373424
Kinetic energy of the rock just before it hits the ground=KE=33000 J
Explanation:
Weight= 2200N
mg=2200
m(9.8)=2200
m=224.5 kg
initial velocity=0
final velocity =V
using kinematic equation V²=Vi²+2gh
V²=0+2 (9.8)(15)
V=17.1 m/s
now kinetic energy= 1/2 mV²
KE= 1/2 (224.5)(17.1)²
KE=33000 J
Thus the kinetic energy of the rock just before it hits the ground=33000 J
Explanation:
According to newtons first law of motion " A body is at a state of rest or uniform motion unless acted upon by a force (external)" which will either
1. change the direction
2. change the acceleration
3. change the velocity(moves or stop the body from moving)
4. change the shape or size