The specific heat of a substance is 0.215 J/g°C. How much energy is required to raise the temperature of 20 g of the substance f
1 answer:
Taking into account the definition of calorimetry and sensible heat, the amount of energy required is 68.8 J.
<h3>Calorimetry</h3>Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.
<h3>Sensible heat</h3>Sensible heat is defined as the amount of heat that a body absorbs or releases without any changes in its physical state (phase change).
In this way, between heat and temperature there is a direct proportional relationship. The constant of proportionality depends on the substance that constitutes the body and its mass, and is the product of the specific heat by the mass of the body.
So, the equation that allows to calculate heat exchanges is:
Q = c× m× ΔT
where:
- Q is the heat exchanged by a body of mass m.
- c is the specific heat substance.
- ΔT is the temperature variation.
In this case, you know:
- Q= ?
- c= 0.215
- m= 20 g
- ΔT= Tfinal - Tinitial= 88 C - 72 C= 16 C
Replacing in the definition of sensible heat:
Q = 0.215 × 20 g× 16 C
Solving:
<u><em>Q=68.8 J</em></u>
Finally, the amount of energy required is 68.8 J.
Learn more about calorimetry:
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Correct question:
Consider the motion of a 4.00-kg particle that moves with potential energy given by
a) Suppose the particle is moving with a speed of 3.00 m/s when it is located at x = 1.00 m. What is the speed of the object when it is located at x = 5.00 m?
b) What is the magnitude of the force on the 4.00-kg particle when it is located at x = 5.00 m?
Answer:
a) 3.33 m/s
b) 0.016 N
Explanation:
a) given:
V = 3.00 m/s
x1 = 1.00 m
x = 5.00
At x = 1.00 m
= 4J
Kinetic energy = (1/2)mv²
= 18J
Total energy will be =
4J + 18J = 22J
At x = 5
= -0.24J
Kinetic energy =
= 2Vf²
Total energy =
2Vf² - 0.024
Using conservation of energy,
Initial total energy = final total energy
22 = 2Vf² - 0.24
Vf² = (22+0.24) / 2
= 3.33 m/s
b) magnitude of force when x = 5.0m
At x = 5.0 m
= 0.016N
The mass that must be added is 0.628 kg
Explanation:
The period of a mass-spring system is given by
where
m is the mass
k is the spring constant
For the initial mass-spring system in the problem, we have
m = 0.500 kg
T = 1.36 s
Solving for k, we find the spring constant:
In the second part, we want the period of the same system to be
T = 2.04 s
Therefore, the mass on the spring in this case must be
Therefore, the mass that must be added is
Learn more about period:
#LearnwithBrainly
Answer:
Bnet=1.006*10^-6T
Explanation:
One long wire lies along an x axis and carries a current of 43 A in the positive x direction. A second long wire is perpendicular to the xy plane, passes through the point (0, 5.9 m, 0), and carries a current of 41 A in the positive z direction. What is the magnitude of the resulting magnetic field at the point (0, 1.7 m, 0)?
the magnetic field Bnet=
the magnetic field due this long wire is given by
B1=∨I1/..............................1
B2=∨I2/............................2
Bnet=.......................3
Bnet=v/2*pi
Bnet=4*pi*10^-7/(2)
Bnet=0.0000002*(641.72)^.5
Bnet=1.006*10^-6T