Correct answer choice is :
C) The freezing and melting temperatures of a substance are the same.
Explanation:
Fluids have a particular temperature at which they convert into solids, identified as their freezing point. In theory, the melting point of a solid should be the same as the freezing point of the liquid. In practice, small variations among these measures can be seen. The freezing point of a matter is the same as that substance's melting point. At this distinct temperature, the substance can exist as either a solid or a liquid. At temperatures below the freezing/ melting point, the substance is a solid.
Answer:
a) x = ⅔ d
, b) the charge must be negative, c) Q
Explanation:
a) In this exercise the force is electric between the charges, we are asked that the system of the three charges is in equilibrium, we use Newton's second law. Balance is on the third load that we are placing
∑ F = 0
-F₁₂ + F₂₃ = 0
F₁₂ = F₂₃
let's replace the values
k Q Q / r₁₂² = k Q 4Q / r₂₃²
Q² / r₁₂² = 4 Q² / r₂₃²
suppose charge 3 is placed at point x
r₁₂ = x
r₂₃ = d-x
we substitute
1 / x² = 4 / (d-x) 2
1 / x = 2 / (d-x)
x = 2 (x-d)
x = 2x -2d
3x = 2d
x = ⅔ d
b) The sign of the charge must be negative, to have an attractive charge on the two initial charges
c) Q
Answer:
At most 2 hours
Explanation:
According to my research of various health departments it is said that cooked food should not be left out in room temperature for more than 2 hours, assuming that room temperature is between 40°F and 140°F. This is because after 2 hours bacteria starts to grow at an increased rate and can have various health effects on the person consuming the food. Therefore food is best wrapped and placed in the refrigerator.
I hope this answered your question. If you have any more questions feel free to ask away at Brainly.
Answer:
a = -8.912 m/s²
Explanation:
Given,
The initial velocity of the car, u = 28 m/s
The final velocity of the car, v = 0
The distance traveled by car, d = 88 m
The velocity displacement relation is given by the formula
v = d/t
∴ t = d/v
Substituting in the above values in the given equation
t = 88/28
= 3.142 s
The acceleration is given by the formula
a = (v-u)/t
= (0 - 28)/3.142
= -8.912 m/s²
The negative sign is that the car is decelerating.
Hence, acceleration a = -8.912 m/s²
