Do you remember the formula for potential energy ?
PE = (mass) (gravity) (height)
If the mass and the height are always the same, then the least PE comes from the least gravity. Surely you can find THAT in the table.
Answer:
(c) 10.29 J
(d) 113.19 J
(e) 113.19 J
(f) 10061 N/m
Explanation:
15 cm = 0.15 m
Let g = 9.8 m/s2
(c) The work done by gravitational force is the product of gravity force and the distance compressed

(d) By using law of energy conservation with potential energy reference being 0 at the maximum compression point. As the ball falls and come to a stop at the compression point, its potential energy is transferred to elastic energy, which is the work that the mattress does on the ball:


where h = 1.5 + 0.15 = 1.65 m is the vertical distance that it falls.

(e) Before the compression, the potential energy of the mattress is 0. After the compression, the potential energy is 113.19J. So it has increased by 113.19J due to the potential energy transferred from the falling ball.
(f) 


Answer
a) charge of the sodium ion is,
q = n e
q = 2.68 x 10¹⁶ x 1.6 x 10⁻¹⁹
q = 4.288 x 10⁻³ C
charge of the chlorine ion is,
q' = n e
q' = 3.92 x 10¹⁶ x 1.6 x 10⁻¹⁹
q' = 6.272 x 10⁻³ C
the current



b) positive ion moves toward negative electrode hence direction of will be in the direction toward negative electrode.
A SWITCH. IT controls the flow of electrons in a circuit
Answer:
Balancing of forces,
In the X-direction:
-Tcos4.5^o +Tcos4.5^o=0
In the Y-direction:
Tsin4.5^o +Tsin4.5^o-m*g=0
2Tsin4.5^o=15*9.81
T=(15*9.81)/(2sin4.5^o)
=937.75 N
Therefore, tension in the rope is 937.75 N.