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
eduard
3 years ago
13

How much heat does a freezer need to remove from 1kg of water at 40°C to make ice at 0°C? (You will need to use the specific hea

t of water to drop the temperature first, before trying to make the phase change!) Show your work.
Physics
1 answer:
Montano1993 [528]3 years ago
3 0

Answer:

Explanation:

Q = m c Δt

heat withdrawn to lower temperature by 40° C

Q = 1 X 1000 X 40 = 40,000 calories.

Q = mL

heat withdrawn to freeze water at 0°C to ice

= 1 x 80000 = 80,000 calories

total heat to be withdrawn = 120,000 calories. = 120,000 x 4.2 = 504 ,000 Joules.

You might be interested in
Write three nuclear equations to represent the nuclear decay sequence that begins with the alpha decay of u-235 followed by a be
vazorg [7]

Answer:

We know that in the decay process the sum of molecular number as well as molecular weight should be constant.

The following three reaction are as follows

1 .

Alpha decay  of parent nuclide

_{92}^{235}\textrm{U} \rightarrow _{90}^{231}\textrm{Th}+_{2}^{4}\textrm{alpha }

The molecular number of alpha particle is 2 and molecular weight is 4 g/mol.

2.

Beta decay of daughter nuclide

_{90}^{231}\textrm{Th}\rightarrow _{91}^{231}\textrm{Pa}+_{-1}^{0}\textrm{beta}+v

v is the neutrino emission,The charge on the beta particle is zero.

3.

Alpha decay

_{91}^{231}\textrm{Pa}\rightarrow_{89}^{227}\textrm{Pa}+_{2}^{4}\textrm{alpha}

5 0
4 years ago
Read 2 more answers
After a 0.320-kg rubber ball is dropped from a height of 19.0 m, it bounces off a concrete floor and rebounds to a height of 15.
GarryVolchara [31]

Answer:

Imp = 11.666\,\frac{kg\cdot m}{s}

Explanation:

Speed experimented by the ball before and after collision are determined by using Principle of Energy Conservation:

Before collision:

(0.32\,kg)\cdot (9.807\,\frac{m}{s^{2}} )\cdot (19\,m) = \frac{1}{2}\cdot (0.320\,kg)\cdot v_{A}^{2}

v_{A} \approx 19.304\,\frac{m}{s}

After collision:

\frac{1}{2}\cdot (0.320\,kg)\cdot v_{B}^{2} = (0.32\,kg)\cdot (9.807\,\frac{m}{s^{2}} )\cdot (15\,m)

v_{B} \approx 17.153\,\frac{m}{s}

The magnitude of the impulse delivered to the ball by the floor is calculated by the Impulse Theorem:

Imp = (0.32\,kg)\cdot [(17.153\,\frac{m}{s} )-(-19.304\,\frac{m}{s} )]

Imp = 11.666\,\frac{kg\cdot m}{s}

5 0
3 years ago
Read 2 more answers
The batteries in the figure above are connected in​
Elena-2011 [213]
The answer is a, series circuit.
5 0
3 years ago
Read 2 more answers
A scientific theory states that the universe is expanding. Which of these statements is correct about this theory?
Stolb23 [73]
A scientific theory states that the universe is expanding. the statement is correct about this theory is: d. it is a well supported explanation which cannot become law. a theory is very different from a law. a theory explain why something happen.

hope this help
8 0
3 years ago
Read 2 more answers
A kayaker needs to paddle north across a 100-m-wide harbor. The tide is going out, creating a tidal current that flows to the ea
Savatey [412]

Answer:

41.81^{\circ}

Explanation:

The tidal current flows to the east at 2.0 m/s and the speed of the kayaker is 3.0 m/s.

Let Vector \overrightarrow{OA} is the tidal current velocity as shown in the diagram.

In order to travel straight across the harbor, the vector addition of both the velocities (i.e the resultant velocity, \vec {R} must be in the north direction.

Let \overrightarrow{AB} is the speed of the kayaker having angle \theta measured north of east as shown in the figure.

For the resultant velocity in the north direction, the tail of the vector \overrightarrow {OA} and head of the vector \overrightarrow{AB} must lie on the north-south line.

Now, for this condition, from the triangle OAB

|\overrightarrow{AB}|\sin \theta=|\overrightarrow{OA}|

\Rightarrow \sin\theta=\frac{|\overrightarrow{OA}|}{|\overrightarrow{AB}|}=\frac 2 3

\Rightarrow \theta=\sin^{-1}\frac23

\Rightarrow \theta=41.81^{\circ}

Hence, the kayaker must paddle in the direction of 41.81^{\circ}  in the north of east direction.

3 0
3 years ago
Other questions:
  • How many constellations are there?
    14·2 answers
  • Which describes uniformitarianism?
    14·1 answer
  • what will be temperature on the kelvin scale if the indicated temperature on the Fahrenheit scale is 200degree Fahrenheit
    7·2 answers
  • Your car is skidding to a stop from a high speed. name all the forces that apply
    12·1 answer
  • Convert 60 miles/hour to m/s (1.6km = 1mile; 1000m = 1km)
    8·1 answer
  • Which factors could be potential sources of error in the experiment? check all that apply.
    11·2 answers
  • The neurons of giant squids, for example, consist of axons with very large radii, which allows the squid to react very quickly w
    15·1 answer
  • II NEED HELP WITH THIS QUESTION PLS
    12·1 answer
  • Ajutor va rog eu repede
    13·1 answer
  • PLEASE PLEASE PLEASE HELP ME, I AM FREAKING OUT BECAUSE REPORT CARDS ARE COMMING SOON AND I REALLY NEED HELP!
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!