Answer:
If you run a 500 W computer for 4 hours, your electric meter will read 2kWh; this is a measure of energy "used". The correct answer is D.
Explanation: Energy is defined as the capacity of doing work and is occurs in different forms( electrical, kinetic, potential energy). Electrical energy consumption can be calculated or measure through the multiplication of the power( W or kW) used by the number of hours during which the power is consumed. Therefore the unit of energy is kWh. From the question,
500W was used for 4 H
Therefore energy consumed
500× 4= 2000Wh. To convert to kWh
Divide by 1000,
2000÷ 1000= 2.
There energy consumed in kWh is,
2kWh energy.
Answer:
The distance between the helicopter and the man changing at that instant is 41.46 ft/sec.
Explanation:
Given:
Distance between the man and the helipad, = ft
Vertical distance between the helipad and the helicopter, = ft
Helicopter lift off vertically and is raising at a speed of 45 ft/sec.
That can be written as, = 45 ft/sec
Now from the diagram (attached with) we can find the hypotenuse of the triangle that is the distance between the man and the helicopter.
Applying Pythagoras theorem:
⇒
⇒
⇒
⇒ ft
Now to find the changing distance between the helicopter and the man we have to differentiate the Pythagoras theorem as dh/dt can be obtained from there.
And we know that the distance b is constant so db/dt=0.
Using chain rule and power rule of differentiation.
⇒
⇒
⇒
⇒ <em>....eliminating the common 2 </em>
⇒
⇒ Plugging the values.
⇒
⇒ ft/sec
So,
41.46 ft/sec is the distance between the helicopter and the man changing at that instant.
Answer:
0.0354 kg/s
Explanation:
= Initial displacement = 0.5 m
= Final displacement = 0.1 m
m = Mass of egg = 55 g
t = Time taken = 5 seconds
Displacement of the oscillator under damping motion is given by
For maximum displacement
From this equation we get
The magnitude of the damping constant is 0.0354 kg/s
Answer:
A.) 42.7 m/s
B.) 0.33 m/s^2
C.) 90 kg
Explanation:
A.) If Justin races his Chevy S-10 down highway 37 north for 2,560 meters in 60 seconds, what is his velocity?
Velocity = displacement/time
Velocity = 2560/60
Velocity = 42.67 m/s
B.) The Chevy S-10 started rounding at 10 meters per hour. What is the acceleration at 30 seconds on the highway?
Acceleration = velocity/time
Acceleration = 10/30
Acceleration = 0.33 m/s^2
C.) The S-10 has a force of 30 N. What is the mass of the car?
Force = mass × acceleration
30 = mass × 0.33
Mass = 30/ 0.33
Mass = 90 kg
Speed is the time rate at which an object is moving along a path, while velocity is the rate and direction of an object's movement. Put another way, speed is a scalar value, while velocity is a vector.