Answer:
i think ice burg for 2nd page for penguin sorry if its wrong!
Explanation:
This question involves the concept of the conservation of energy.
(a) The child's speed halfway will be "12.13 m/s".
(b) The child's speed three-fourth way will be "14.86 m/s".
(a)
Using the <em>law of conservation of energy</em>:
Potential Energy Lost = Kinetic Energy Gained

where,
v = speed = ?
g = acceleration due to gravity = 9.81 m/s²
h = height lost = halfway = height/2 = 15 m/2 = 7.5 m
Therefore,

<u>v = 12.13 m/s</u>
<u />
(b)
Using the <em>law of conservation of energy</em>:
Potential Energy Lost = Kinetic Energy Gained

where,
v = speed = ?
g = acceleration due to gravity = 9.81 m/s²
h = height lost = three-fourth way down = 
Therefore,

<u>v = 14.86 m/s</u>
<u />
Learn more about the <em>law of conservation</em> of energy here:
brainly.com/question/20971995?referrer=searchResults
The attached picture shows the <em>law of conservation of energy</em>.
d = distance between the two point charges = 60 cm = 0.60 m
r = distance of the location of point "a" where the electric field is zero from charge
between the two charges.
= magnitude of charge on one charge
= magnitude of charge on other charge
= 3 
= Electric field by charge
at point "a"
= Electric field by charge
at point "a"
Electric field by charge
at point "a" is given as
= k
/r²
Electric field by charge
at point "a" is given as
= k
/(d-r)²
For the electric field to be zero at point "a"
=
k
/(d-r)² = k
/r²
/(d-r)² = 3
/r²
1/(0.60 - r)² = 3 /r²
r = 0.38 m
r = 38 cm
Answer: 40 J
Explanation: Work is equal to the product of force and distance.
W = Fd
= 4N ( 10 m)
= 40 J
Answer:
B. 45.0 kg
Explanation:
On earth the object has ;
Mass = 45 kg
acceleration = 9.81 m/s²
On Jupiter, acceleration is 24.79 m/s²
The mass of this object on Jupiter will be 45 kg. It will not change. Mass of an object will only change when you remove part of the object from it or add to it another part. The mass is the same on Earth and on Jupiter. However, due to increased acceleration on Jupiter , the weight will change/ increase because;
Weight = mass * acceleration
<u>On Earth </u>
Weight of the object will be : 45 * 9.81 = 441.45 kg
<u>On Jupiter</u>
Weight of the object will be : 45*24.79 =1115.55 kg