Answer:
Overloading the muscles causes them to get stronger and grow larger.
Answer:
<em>Physical change: </em>(a) grinding of glass, (c) burning of candle, (d) sanding wood
<em>Chemical change: </em>(b) rusting of iron.
Explanation:
Physical Change: This is the type of change a matter undergoes, it is easily reversible and no new substance is formed.
Chemical Change: Is one which is not easily reversible and a new substance is formed.
From the question above, the following changes can be classified into physical or chemical change
<em>Physical change: </em>(a) grinding of glass, (c) burning of candle, (d) sanding wood
<em>Chemical change: </em>(b) rusting of iron
A
Because it is the only one that show an increase in both the temperature and rate or reaction
According to the law of reflection, When a ray of light passes from rarer medium to denser medium , it bends towards the normal. So, if there is a transparent material that is more dense than glass then the ray of light will bend towards the normal. The direction of light through the medium is predicted by Snell's Law. According to the Snell's law:
n₁ sin θ₁ = n₂ sin θ₂
Where n₁ is the refractive index of the first medium
n₂ is the refractive index of second medium.
θ₁ and θ₂ are the angle of incidence of light in medium 1 and medium 2
Answer:
N = 198.3 N, fr = 126.98 N and μ = 0.64
Explanation:
For this exercise we must use the translational equilibrium condition.
Let's set a reference system with the x-axis horizontally and the y-axis vertical. Let's use trigonometry to decompose the applied force
cos θ = Fₓ / F
sin θ = F_y / F
Fₓ = F cos θ
F_y = F sin θ
Fₓ = 159 cos 37 = 126.98 N
F_y = 159 sin 37 = 95.69 N
Y axis
N + F_y - W = 0
N = W - F_y
N = 294 - 95.69
N = 198.3 N
X axis
Fₓ -fr = 0
Fₓ = fr
fr = 126.98 N
the expression for the friction force is
fr = μ N
μ = fr / N
μ = 126.98 / 198.3
μ = 0.64
