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
Bess [88]
2 years ago
11

An electric drill transfers 200 J of energy into a useful kinetic energy store. It also transfers 44 J of energy by sound and 48

J of energy by heat. What is the efficiency of this drill? Round your answer to the nearest whole number
Physics
1 answer:
kramer2 years ago
3 0

Answer:

Er = 108 [J]

Explanation:

To solve this problem we must understand that the total energy is 200 [J]. Of this energy 44 [J] are lost in sound and 48 [J] are lost in heat. In such a way that these energy values must be subtracted from the total of the kinetic energy.

200 - 44 - 48 = Er

Where:

Er = remaining energy [J]

Er = 108 [J]

You might be interested in
A snail crawls 300 cm in 1 hour. Calculate the snail's speed in each of the following units. A) cm/h B) cm/min C) m/h
Crazy boy [7]
A) 300cm/h
B)1 hr=60 min
300/60=5
5cm/min
C)1m=100cm
300/100=3
3m/h
7 0
3 years ago
Hooke's law describes a certain light spring of unstretched length 33.6 cm. when one end is attached to the top of a doorframe a
masha68 [24]
Missing question: "What is the spring's constant?"

Solution:
The object of mass m=6.89 kg exerts a force on the spring equal to its weight:
F=mg=(6.89 kg)(9.81 m/s^2)=67.6 N
When the object is attached to the spring, the displacement of the spring with respect to its equilibrium position is
\Delta x=43.2 cm-33.6 cm=9.6 cm=0.096 m
And by using Hook's law, we can find the constant of the spring:
k= \frac{F}{\Delta x}= \frac{67.6 N}{0.096 m}=704.2 N/m
4 0
3 years ago
1. (30 pts) Let x(t) = cos(πt/2) be a continuous-time signal,
posledela

Given that the function of the wave is f(x) = cos(π•t/2), we have;

a. The graph of the function is attached

b. 4 units of time

c. Even

d. 4.935 J/kg

e. 1.234 W/kg

<h3>How can the factors of the wave be found?</h3>

a. Please find attached the graph of the signal created with GeoGebra

b. The period of the signal, T = 2•π/(π/2) = <u>4</u>

c. The signal is <u>even</u>, given that it is symmetrical about the y-axis

d. The energy of the signal is given by the formula;

\frac{1}{2}  \cdot  \mu^{2} \cdot \omega ^{2}  \cdot \:  {a}^{2}  \times  \lambda

Which gives;

E = 0.5 × 1.571² × 1² × 4 = <u>4.935 J/kg</u>

e. The power of the wave is given by the formula;

E = 0.5 × 1.571² × 1² × 4 × 0.25 = <u>1.234 W/</u><u>kg</u>

Learn more about waves here:

brainly.com/question/14015797

8 0
2 years ago
A girl travels 20 miles on her bike, the trip takes two hours. express her speed in miles/hr
xxTIMURxx [149]

Answer:

10 mph

Explanation:

6 0
2 years ago
Predict whether the changes in enthalpy, entropy, and free energy will be positive or negative for the melting of ice, and expla
BlackZzzverrR [31]
  <span>Melting of ice is an endothermic process, meaning that energy is absorbed. When ice spontaneously melts, ΔH (change in enthalpy) is "positive". ΔS (entropy change) is also positive, because, becoming a liquid, water molecules lose their fixed position in the ice crystal, and become more disorganized. ΔG (free energy of reaction) is negative when a reaction proceeds spontaneously, as it happens in this case. Ice spontaneously melts at temperatures higher than 0°C. However, liquid water also spontaneously freezes at temperatures below 0°C. Therefore the temperature is instrumental in determining which "melting" of ice, or "freezing" of water becomes spontaneous. The whole process is summarized in the Gibbs free energy equation: 
ΔG = ΔH – TΔS</span>
4 0
3 years ago
Other questions:
  • Mike is watching a Disney movie with his son Jason Jason likes the movie so much that he becomes excited and stands in front of
    15·1 answer
  • PLEASE ANSWER...... Suppose a car is traveling in the negative x-direction and comes to a stop. What is the sign of that car’s a
    15·2 answers
  • Answer the following questions.
    5·1 answer
  • Iron (II) hydroxide, whose chemical formula is shown here, is soluble in different solutions. In which solution would the Iron (
    12·1 answer
  • What types of landforms can water form?
    5·2 answers
  • In what unit do we measure the work done by a force
    9·1 answer
  • Determine the speed of a falling object 7.8 sec after it dropped.
    8·1 answer
  • A car is moving with 15000J of energy. If the car has a mass of 1500kg, how fast is it moving?
    10·1 answer
  • Which statement is true of gravity?
    10·1 answer
  • Use of lubricants increase efficency of machine​
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!