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
weeeeeb [17]
3 years ago
12

Maye is running an experiment to determine if a car with large tires will move faster than a car with small tires. her ramp is 0

.7 m long she recording the following times on each of her trials: Trial 1:2.5 seconds, Trial 2: 2.75 seconds, Trial 3: 2.98 seconds. what was the average speed of her car?
Physics
1 answer:
Digiron [165]3 years ago
3 0

Answer:

0.256 m/s

Explanation:

Speed is distance over time.

Find the speed of each trial and then find the average.

Trial 1: v = 0.7 m / 2.5 s = 0.280 m/s

Trial 2: v = 0.7 m / 2.75 s = 0.255 m/s

Trial 3: v = 0.7 m / 2.98 s = 0.235 m/s

v_avg = (0.280 m/s + 0.255 m/s + 0.235 m/s) / 3

v_avg = 0.256 m/s

Round as needed.

You might be interested in
When did forensic science start to become influential in solving crimes?
Dafna11 [192]

1900s -- 1980s

Forensic science R&D in the 1980s

6 0
2 years ago
If there is no change in the velocity of the object then it is known to be in ______
irga5000 [103]

OPTION (C) IS CORRECT

ANSWER - UNIFORM MOTION

If there is no change in the velocity of the object then it is known to be in <u>UNIFORM MOTION</u>.

EXPLORE MORE:-

EXAMPLE - A CAR COVERS A DISTANCE OF 15 KM WE'D EVERY 2 HOURS

FOR AN UNIFORM MOTION, ACCELERATION IS ZERO , AS THERE IS NO CHANGE IN VELOCITY....

-THANKS.!!

4 0
2 years ago
Steam enters an adiabatic turbine at 6 MPa, 600 ℃, and 80 m/s and leaves at 50 kPa, 100 ℃, and 140 m/s. If the power output of t
lisabon 2012 [21]

Answer:

W(r,out) = 5.81 MW

\eta = 86.1 %

Explanation:

we use here steam table for get value of h1, s1 etc

so use for 6MPa and 600 degree

Enthalphy of steam h1 = 3658.8 kJ/kg

Entropy of steam s 1 is = 7.1693 kJ /kg.K

and

for 50 kPa and 100 degree

Enthalphy of steam h2 = 2682.4 kJ/kg

Entropy of steam s2 is = 7.6953 kJ /kg.K

so we use here energy balance equation that is

m\times(h1 + \frac{v1^2}{2} = m\times(h2 + \frac{v2^2}{2} + W(out)      ..............1

put here value and we get m

m = \frac{5\times1000}{3658.8-2682.4+\frac{80^2-140^2}{2}\times \frac{1}{1000}}  

solve it we get

m = 5.156 kg/s

so by energy balance equation

m\psi1 = m\psi2 + W(r,out)

W(r,out) = m(\psi1 -\psi2)

W(r,out) = h1 - h2 + ΔKE + ΔPE - To(s1-s2)

W(r,out) = m[h1-h2+ \frac{v1^2-v^2}{2}- To (s1-s2)

W(r,out) = W(a,out) - m.To.(s1-s2)     ........................2

put here value

W(r,out) = 5000 - ( 5.156 × (25 + 273) ×( 7.1693 - 7.6953)

W(r,out) = 5908.19 = 5.81 MW

and

second law deficiency is

\eta = \frac{W(a,out)}{W(r,out)}     ..............................3

put here value

\eta = \frac{5}{5.81}

\eta = 86.1 %

6 0
3 years ago
How do you change the currents in a circuit
mel-nik [20]
-
Eddy Current Testing

Introduction
Basic Principles
History of ET
Present State of ET

The Physics
Properties of Electricity
Current Flow & Ohm's Law
Induction & Inductance
Self Inductance
Mutual Inductance
Circuits & Phase
Impedance
Depth & Current Density
Phase Lag

Instrumentation
Eddy Current Instruments
Resonant Circuits
Bridges
Impedance Plane
Display - Analog Meter

Probes (Coils)
Probes - Mode of Operation
Probes - Configuration
Probes - Shielding
Coil Design
Impedance Matching

Procedures Issues 
Reference Standards
Signal Filtering

Applications
Surface Breaking Cracks
SBC using Sliding Probes
Tube Inspection 
Conductivity 
Heat Treat Verification
Thickness of Thin Mat'ls
Thickness of Coatings

Advanced Techniques
Scanning
Multi-Frequency Tech.
Swept Frequency Tech.
Pulsed ET Tech.
Background Pulsed ET
Remote Field Tech.

Quizzes

Formulae& Tables
EC Standards & Methods
EC Material Properties
-






Current Flow and Ohm's Law

Ohm's law is the most important, basic law of electricity. It defines the relationship between the three fundamental electrical quantities: current, voltage, and resistance. When a voltage is applied to a circuit containing only resistive elements (i.e. no coils), current flows according to Ohm's Law, which is shown below.

I = V / R 

Where: 

I =

Electrical Current (Amperes)

V =

Voltage (Voltage)

R =

Resistance (Ohms)

    

Ohm's law states that the electrical current (I) flowing in an circuit is proportional to the voltage (V) and inversely proportional to the resistance (R). Therefore, if the voltage is increased, the current will increase provided the resistance of the circuit does not change. Similarly, increasing the resistance of the circuit will lower the current flow if the voltage is not changed. The formula can be reorganized so that the relationship can easily be seen for all of the three variables.

The Java applet below allows the user to vary each of these three parameters in Ohm's Law and see the effect on the other two parameters. Values may be input into the dialog boxes, or the resistance and voltage may also be varied by moving the arrows in the applet. Current and voltage are shown as they would be displayed on an oscilloscope with the X-axis being time and the Y-axis being the amplitude of the current or voltage. Ohm's Law is valid for both direct current (DC) and alternating current (AC). Note that in AC circuits consisting of purely resistive elements, the current and voltage are always in phase with each other.

Exercise: Use the interactive applet below to investigate the relationship of the variables in Ohm's law. Vary the voltage in the circuit by clicking and dragging the head of the arrow, which is marked with the V. The resistance in the circuit can be increased by dragging the arrow head under the variable resister, which is marked R. Please note that the vertical scale of the oscilloscope screen automatically adjusts to reflect the value of the current.

See what happens to the voltage and current as the resistance in the circuit is increased. What happens if there is not enough resistance in a circuit? If the resistance is increased, what must happen in order to maintain the same level of current flow?


4 0
4 years ago
Consider a lawnmower of mass m which can slide across a horizontal surface with a coefficient of friction μ. In this problem the
inna [77]

Answer:

Fh = u*m*g / (cos(θ) - u*sin(θ))

Explanation:

Given:

- The mass of lawnmower = m

- The angle the handle makes with the horizontal = θ

- The force applied along the handle = Fh

- The coefficient of friction of the lawnmower with ground = u

Find:

Find the magnitude, Fh, of the force required to slide the lawnmower over the ground at constant speed by pushing the handle.

Solution:

- Construct a Free Body Diagram (FBD) for the lawnmower.

- Realize that there is horizontal force applied parallel to ground due to Fh that drives the lawnmower and a friction force that opposes this motion. We will use to Newton's law of motion to express these two forces in x-direction as follows:

                                     F_net,x = m*a

- Since, the lawnmower is to move with constant speed then we have a = 0.

                                     F_net,x = 0

- The forces as follows:

                                     Fh*cos(θ) - Ff = 0

Where, Ff is the frictional force:

                                     Fh = Ff /cos(θ)

Similarly, for vertical direction y the forces are in equilibrium. Using equilibrium equation in y direction we have:

                                    - W - Fh*sin(θ) + Fn = 0

Where, W is the weight of the lawnmower and Fn is the contact force exerted by the ground on the lawnmower. Then we have:

                                     Fn = W + Fh*sin(θ)

                                     Fn = m*g + Fh*sin(θ)

The Frictional force Ff is proportional to the contact force Fn by:

                                     Ff = u*Fn

                                     Ff = u*(m*g + Fh*sin(θ))

Substitute this expression in the form derived for Fh and Ff:

                                     Fh*cos(θ) = u*(m*g + Fh*sin(θ))

                                     Fh*(cos(θ) - u*sin(θ)) = u*m*g

                                     Fh = u*m*g / (cos(θ) - u*sin(θ))

5 0
3 years ago
Other questions:
  • after an investigation kuri determines that her hypothesis was wrong what is the best thing for kuri to do next​
    10·2 answers
  • Which statement BEST explains why the specific heat of water is higher than the specific heat of most other substances?
    6·2 answers
  • A plane has a cruising speed of 250 miles per hour when there is no wind. at this speed, the plane flew 300 miles with the wind
    11·1 answer
  • Estimate the change in gravitational potential energy when a person with mass 80 kg rise from bed to a standing position. Assumi
    5·1 answer
  • A small steel wire of diameter 1.0 mm is connected to an oscillator and is under a tension of 7.5 N. The frequency of the oscill
    6·1 answer
  • A boulder that is resting on the top of a cliff slips over the edge and accelerates towards the ground. As the rock falls, the a
    15·2 answers
  • What is intermolecular forces and how is it related to phases of matter
    6·1 answer
  • You’ve just completed a survey of the wireless signals traversing the airspace in your employer’s vicinity, and you’ve found an
    11·1 answer
  • A screen is placed a distance dd to the right of an object. A converging lens with focal length ff is placed between the object
    14·1 answer
  • electric generator consists of a circular coil of wire of radius 4.0×10−2 m , with 20 turns. The coil is located between the pol
    12·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!