1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Digiron [165]
3 years ago
9

An unknown material, m1 = 0.49 kg, at a temperature of T1 = 92 degrees C is added to a Dewer (an insulated container) which cont

ains m2 = 1.1 kg of water at T2 = 21 degrees C. Water has a specific heat of cw = 4186 J/(kg⋅K). After the system comes to equilibrium the final temperature is T = 31 degrees C. Detemine the specific heat of unknown material.
Physics
1 answer:
erastova [34]3 years ago
3 0

Answer:

c_u=1540.5J/kg^{\circ}K

Explanation:

We know that heat relates to mass, specific heat and variation of temperature experimented because of this heat through the equation Q=mc\Delta T=mc(T_f-T_i). The heat released by the unknown material is absorbed by water, so we have Q_u=-Q_w, and we can write:

m_uc_u(T_{uf}-T_{ui})=-m_wc_w(T_{wf}-T_{wi})

Since thermal equilibrium is reached we know that T_{cf}=T_{wf}=T_f=31^{\circ}C=304^{\circ}K, where we have added 273^{\circ} to convert the temperature from Celsius to Kelvin, as <em>we must do</em>. Since we want the specific heat of the unknown material, we do:

c_u=-\frac{m_wc_w(T_f-T_{wi})}{m_u(T_f-T_{ui})}

Which for our values is:

c_u=-\frac{(1.1kg)(4186J/kg^{\circ}K)((304^{\circ}K)-(294^{\circ}K))}{(0.49kg)((304^{\circ}K)-(365^{\circ}K))}=1540.5J/kg^{\circ}K

You might be interested in
An electric motor rotating a workshop grinding wheel at 1.06 102 rev/min is switched off. Assume the wheel has a constant negati
kvasek [131]

Answer:

t = 106π / 30*2.1

Explanation:

w_{i} = 1.06*10^{2}    => 106

    => 106 x 2π/60

    => 106/30π

∝ = -2.1 rad/sec²

w_{f} => 0

w_{f} = w_{i} + ∝t

∴ (w_{f} - w_{i}) / ∝ = t

t = 106π / 30*2.1

6 0
3 years ago
A car with a mass of 2000 kg is moving around a circular curve at a uniform velocity of 25 m/s per second. The curve has a radiu
IrinaK [193]
The centripetal force is:
 F = mv² / R
 Where:
 m: mass of the object
 v: object speed
 R: radius of the curve.
 We have to:
 m = 2000kg
 v = 25 m / s
 R = 80 meters.
 Then the centripetal force acting on the vehicle is:
 F = (2000kg * (25m / s) ²) / 80m
 F = 15625 N
4 0
3 years ago
Calculate the tangential speed of a yo-yo twirled at the end of a 4 meter long string at 2 revolutions per second.
Oliga [24]

Answer: 50 m/s

Explanation: speed v = 2· pi·n·r = 2· 3.14· 2 s^-1· 4 m

8 0
2 years ago
In your own words, explain why we see a rainbow or colorful sunset. Explain the properties and interactions that make this displ
Maksim231197 [3]
Wee see rainbows due to the geometries of the raindrops. when the sun shines behind, rays of light enter the raindrops and this light are refracted. The lights are then reflected from the back of the raindrop and refracted again as it passes the rain drop. Refraction in this sense is the cause for splitting the light into several colors.
7 0
3 years ago
A student, Daniela, is arguing that since a meteor is weightiess in space, if it crashes
zmey [24]

Answer:

she's wrong because she is and there it doesn't say she's right

5 0
2 years ago
Other questions:
  • A stone weighing 1.5 kilograms is resting on a rock at a height of 20 meters above the ground. The stone rolls down 10 meters an
    11·2 answers
  • Data: Atom Element Protons Neutrons Electrons Net Charge Mass Number 1 2 3 4
    11·1 answer
  • 11 Initially, a single resistor R 1 is wired to a battery. Then resistorR 2 is added in parallel. Are (a) the potential differen
    13·1 answer
  • you push a book a distance of 5 meters with a force of 10 newtons for 2 seconds how much work did you do on the book
    14·1 answer
  • A circuit has resistors R 1 = 468 Ω and R 2 = 125 Ω R1=468 Ω and R2=125 Ω , and two batteries V 1 = 12.0 V and V 2 = 3.00 V V1=1
    14·1 answer
  • ________is what causes acceleration. Two forces acting opposite each other.
    13·1 answer
  • Two tugboats pull a disabled supertanker. Each tug exerts a constant force of 2.20×106 N , one at an angle 15.0 ∘ west of north,
    6·1 answer
  • A net force of 10.0 N causes an object to accelerate at 2.00m/s^2. What is the mass of the object?
    12·1 answer
  • Friction _____moving things and turns motion energy into _____
    9·1 answer
  • A car goes from 0 to 100 km/hr in 10 seconds. What is its acceleration
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!