Answer:
increase in temperature of water is 10° C
Explanation:
Given data
pizza = 500 kcal = 500000 calories
cold water = 50 L
to find out
increase in temperature of water
solution
we know heat formula that is
heat = m × specific heat × Δt
here m is mass = 50000 gram and Δt is change in temperature
and specific heat = 1 cal / gram C
so put here all value and find Δt
500000 = 50000 × 1 × Δt
Δt = 10° C
so increase in temperature of water is 10° C
Answer:
See the answers below.
Explanation:
to solve this problem we must make a free body diagram, with the forces acting on the metal rod.
i)
The center of gravity of the rod is concentrated in half the distance, that is, from the end of the bar to the center there is 40 [cm]. This can be seen in the attached free body diagram.
We have only two equilibrium equations, a summation of forces on the Y-axis equal to zero, and a summation of moments on any point equal to zero.
For the summation of forces we will take the forces upwards as positive and the negative forces downwards.
ΣF = 0

Now we perform a sum of moments equal to zero around the point of attachment of the string with the metal bar. Let's take as a positive the moment of the force that rotates the metal bar counterclockwise.
ii) In the free body diagram we can see that the force acts at 18 [cm] of the string.
ΣM = 0
![(15*9) - (18*W) = 0\\135 = 18*W\\W = 7.5 [N]](https://tex.z-dn.net/?f=%2815%2A9%29%20-%20%2818%2AW%29%20%3D%200%5C%5C135%20%3D%2018%2AW%5C%5CW%20%3D%207.5%20%5BN%5D)
Force = mass * acceleration = 1500kg * 8m/s²
With the addition of vectors we can find that the correct answer is:
C) Q> P > R = S > T
The addition of vectors must be done taking into account that they have modulus and direction. The analytical method is one of the easiest methods, the method to do it is:
- Set a Cartesian coordinate system
- Decompose vectors into their components in a Cartesian system
- Perform the algebraic sums on each axis
- Find the resultant vector using the Pythagoras' Theorem to find the modulus and trigonometry to find the direction.
In this exercise indicate that the modulus of all vectors is the same, suppose that the value of the modulus is A.
We fix a Cartesian coordinate system with the horizontal x axis and the vertical y axis, we can see that we do not need to perform any decomposition, so we perform the algebraic sums
Diagram P
x-axis
x = 2A
y-axis
y = 2A
The modulus of the resulting vector can be found with the Pythagorean Theorem
P =
P =
P = 2 √2 A
Diagram Q
x-axis
x = 3A
y-axis
y = A
Resulting
Q =
Q =
Q = 
Diagram R
x- axis
x = 0
y-axis
y = 2 A
Resulting
R =
R =
Diagram S
x-axis
x = 2 A
y-axis
y = 0
Resulting
S = 2A
Diagram T
x- axis
x = 0
y-axis
y = 0
Resultant T = 0
We order the diagram from highest to lowest
Q> P> R = S> T
When reviewing the different answers, the correct one is:
C. Q> P> R = S> T
Learn more about adding vectors here:
brainly.com/question/14748235