<h3>
Answer: 130 newtons</h3>
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Explanation:
We'll need the acceleration first.
- The initial speed (let's call that Vi) is 8.0 m/s
- The final speed (Vf) is 0 m/s since Sam comes to a complete stop at the end.
- This happens over a duration of t = 4.0 seconds
The acceleration is equal to the change in speed over change in time
a = acceleration
a = (change in speed)/(change in time)
a = (Vf - Vi)/(4 seconds)
a = (0 - 8.0)/4
a = -8/4
a = -2
The acceleration is -2 m/s^2, meaning that Sam slows down by 2 m/s every second. Negative accelerations are often associated with slowing down. The term "deceleration" can be used here.
Here's a further break down of Sam's speeds at the four points of interest
- At 0 seconds, he's going 8 m/s
- At the 1 second mark, he's slowing down to 8-2 = 6 m/s
- At the 2 second mark, he's now at 6-2 = 4 m/s
- At the 3 second mark, he's at 4-2 = 2 m/s
- Finally, at the 4 second mark, he's at 2-2 = 0 m/s
Next, we'll apply Newton's Second Law of motion
F = m*a
where,
- F = force applied
- m = mass
- a = acceleration
We just found the acceleration, and the mass is fairly easy as all we need to do is add Sam's mass with the sled's mass to get 60+5.0 = 65 kg
So the force applied must be:
F = m*a
F = 65*(-2)
F = -130 newtons
This force is negative to indicate it's pushing against the sled's momentum to slow Sam down.
The magnitude of this force is |F| = |-130| = 130 newtons
Answer:
Explanation:
Electrical energy is energy derived from electric potential energy or kinetic energy.
Or,
Electrical energy is a form of energy resulting from the flow of electric charge. Lightning, batteries and even electric eels are examples of electrical energy.People use electricity for lighting, heating, cooling, and refrigeration and for operating appliances, computers, electronics, machinery, and public transportation systems.
Hope it helped you.
Answer:C..net work done on the object.
Explanation:
Answer:
The wavelength of these signals is as follow:
- Wavelength of 550 kHz is 545.45 m
- Wavelength of 1600 kHz is 187.5 m
Explanation:
Given that:
Frequency = 550 kHz & 1600 kHz
Velocity = 3.0 x 10⁸ m/s
As we know that frequency is expressed by the following equation:
- Frequency = Velocity / Wavelength ---- (1)
For 550 kHz:
The equation can be rearranged as
Wavelength = Velocity / Frequency
Wavelength = (3.0 x 10⁸ m/s) / (550 x 1000 Hz)
Wavelength = 545.45 m
For 1600 kHz:
Wavelength = Velocity / Frequency
Wavelength = (3.0 x 10⁸ m/s) / (1600 x 1000 Hz)
Wavelength = 187.5 m
