Answer:
1.503 J
Explanation:
Work done in stretching a spring = 1/2ke²
W = 1/2ke²........................... Equation 1
Where W = work done, k = spring constant, e = extension.
Given: k = 26 N/m, e = (0.22+0.12), = 0.34 m.
Substitute into equation 1
W = 1/2(26)(0.34²)
W = 13(0.1156)
W = 1.503 J.
Hence the work done to stretch it an additional 0.12 m = 1.503 J
Complete Question:
Which process is not required for an animal to obtain energy from food?
a. Secretion.
b. Digestion.
c. Excretion.
d. Ingestion.
Answer:
c. Excretion.
Explanation:
Excretion is a metabolic process in which living organisms gets their system rid of metabolic waste, water and excess ions. This is usually done with the aid of kidney, skin and lungs in all vertebrates.
Example of excretions are urination, sweating and defecation.
<h2>
Depth of river is 4.48 m</h2>
Explanation:
Discharge = Area x Velocity
Discharge of river = Discharge of stream 1 + Discharge of stream 2

Area of stream 1 = w₁ x d₁ = 8.9 x 3.8 = 33.82 m²
Area of stream 2 = w₂ x d₂ = 6.5 x 3.9 = 25.35 m²
Velocity of stream 1 = 2.3 m/s
Velocity of stream 2 = 2.6 m/s
Velocity of river = 3 m/s

Substituting

Depth of river = 4.48 m
Answer:
A. Thermal energy;
Thermal energy is energy that comes from a substance whose molecules and atoms are vibrating faster due to a rise in temperature.
Answer:
D. 21 ml
Explanation:
Since, the cylinder is marked and graduated in the intervals if 1 ml. Therefore, the values between two consecutive ml, such as between 30 ml and 31 ml can not be determined. Because, we do not have any scale in between the ml. So, the least count of this instrument is 1 ml. This graduated cylinder can give the answers to zero decimal places, accurately. And it can not determine any decimal value due to its graduating or the marking limitation. So, all the options given, contain a decimal value, except for the option D. In option D there is no decimal value, hence it is a correct answer.
D. <u>21 ml</u>