Answer:
D) Roger is incorrect. Only a chemical change is taking place as evidenced by the light and heat of the burning candles.
Explanation:
- A physical change is a change in which there is no formation of new substances. Examples of physical changes are the melting or the evaporation of a substance (all phase transitions are examples of physical changes): in such cases, there is no formation of new substances.
- A chemical change is a change in which new substances form. Examples of chemical changes are the chemical reactions: for instance, when a candle burns, a reaction is taken place (oxygen is burnt, transforming into carbon dioxide + heat + light, so this is an example of chemical change).
Therefore, the correct answer is
D) Roger is incorrect. Only a chemical change is taking place as evidenced by the light and heat of the burning candles.
Answer:
Even though the sun is much more massive and therefore has stronger overall gravity than the moon, the moon is closer to the earth so that its gravitational gradient is stronger than that of the sun.
Explanation:
V = l x w x h
v = 3 x 6 x 4
v = 72
Answer:
a) 72mJ
b) 0.33m/s
c) 54mJ
d) 18mJ
Explanation:
(a) The total energy of the system is given by:

where k is the force constant and A is the amplitude. By replacing we get:
= 72mJ
(b) we can get the speed by the conservation of energy (the kinetic energy and potential energy must equal the total energy in any place):

where we have used that x=1.15cm=0.0115m; A=6.00cm=0.06m
(c) Again, by the conservation of energy:

(d) 
hope this helps!!
Answer
mass of pellet (m₁) =1.3 g
mass of the system when pellet sticks to the cheese is (m₂)
m₂ = 109 + 1.3 = 110.3 g
velocity of the muzzle = 73 m/s
now using conservation of momentum
m₁ v₁ =m₂v₂
where v₁ is velocity of the pellet and v₂ is the initial velocity of the (pellet+cheese ) system
m₁ v₁ =m₂v₂
1.3 x 73 = 110.3 x v₂
v₂ = 0.86 m/s
initial velocity of (pellet+cheese)system = v₁
and final velocity = 0
using
v₁² - 0 = 2 a s
where a is the deceleration and s =25 cm
0.86² - 0 = 2 a s
0.86² - 0 = 2 x a x 0.25
a = 1.48 m/s²
now, calculation of force of friction
m₂ a = μ m₂ g

where μ is the coefficient of friction

μ = 0.087