Answer:
C
Sign-Negative
Explanation:
We are given that
Electric field =
(Radially downward)
Acceleration=
(Upward)
Mass of charge=3 g=
kg
1kg=1000g
We have to find the magnitude and sign of charge would have to be placed on a penny .
By newton's second law


Substitute the values then we get

Substitute the values then we get




C
Sign of charge =Negative
Because electric force acting in opposite direction of electric field therefore,charge on penny will be negative.
If the object's kinetic energy is zero, then due to in multiplication factor, it's momentum will also be equal to zero 'cause the velocity of the object must be Nil
In short, Your Answer would be: "Zero"
Hope this helps!
Answer:
1. You push on the ball and the ball pushes on your hand
.
2. The ball hits the ground and the ground pushes back on the ball
.
3. You walk on the ground with your feet and the ground pushes back on you.
Explanation:
A concave mirror is opaque whereas a concave lens is transparent. ... Difference between concave mirror and concave lens is A concave mirror is opaque whereas a concave lens is transparent. A concave mirror causes reflection of light whereas a concave lens causes refraction of light.