Answer: I = 3.6 m3
(C)
Explanation:
moment of inertia for spherically shaped object around it's center is given as
I = (2/5) mr²
substituting the r = 3m²
I = (2/5)*(9) m3
I = 3.6 m3
Answer;
It does not have an hypothesis
Explanation;
The goal of descriptive investigation is to describe. It should provide factual, accurate and systematic descriptions of phenomena without attempting to infer causal relationships. It does not answer questions about the how, when, or why a particular phenomenon occurred.
A descriptive investigation includes a question but no hypothesis. Observations are recorded, but no comparisons are made and no variables are manipulated.
Answer:
b. The reflection of light from a smooth surface is called specular reflection.
c. The reflection of light from a rough surface is called diffuse reflection.
Explanation:
a. The angle of incidence is equal to the angle of reflection only when a ray of light strikes a plane mirror.
This is wrong: Based on law of reflection "The angle of incidence is equal to the angle of reflection when light strikes any plane surface" examples plane mirrors, still waters, plane tables, etc
b. The reflection of light from a smooth surface is called specular reflection.
This is correct
c. The reflection of light from a rough surface is called diffuse reflection.
This is correct
d. For diffuse reflection, the angle of incidence is greater than the angle of reflection.
This is wrong: the angle of incident is equal to angle of reflection. The only difference between this type of reflection and specular reflection, is that the normal for diffuse reflection is not parallel to each due to the rough surface in which the light incidents.
For specular reflection, the angle of incidence is less than the angle of reflection.
This is wrong: the angle of incident is equal to angle of reflection
Answer:
The equivalent resistance of the parallel circuit would be 20 Ω
Explanation:
To calculate the resistance of resistors connected in parallel, the formula to be used is
1/R = 1/R₁ + R₂ + R₃ + R₄...
1/R = 1/120 + 1/60 + 1/40
1/R = (1 + 2 + 3)/120
1/R = 6/120
1/R = 1/20 Ω
This can be rewritten or cross-multiplied to be
R × 1 = 20 × 1
R = 20 Ω
The equivalent resistance (R) would then be 20 Ω