The force exerted on the car during the stop measures 6975 N.
Explanation: Given that the mass (m) is 930 kg, speed (s) at 56 km/h converts to 15 m/s, and the stopping time (t) is 2 s, we compute the force using F = m * a. Here, acceleration (a) can be obtained through a = s/t. The total force calculation confirms that F = 930 kg * (15 m/s) / 2 s results in 6975 N.
Δd = 23 cm. When the eta string of the guitar has nodes at both ends, the resulting waves create a standing wave, which can be expressed with the following formulas: Fundamental: L = ½ λ, 1st harmonic: L = 2 ( λ / 2), 2nd harmonic: L = 3 ( λ / 2), Harmonic n: L = n λ / 2, where n is an integer. The rope's speed can be calculated using the formula v = λ f. This speed remains constant based on the tension and linear density of the rope. Now, let's determine the speed with the provided data: v = 0.69 × 196, yielding v = 135.24 m/s. Next, we will find the wavelengths for the two frequencies: λ₁ = v / f₁, which gives λ₁ = 135.24 / 233.08, equaling λ₁ = 0.58022 m; λ₂ = v / f₂ results in λ₂ = 135.24 / 246.94, consequently λ₂ = 0.54766 m. We'll substitute into the resonance equation Lₙ = n λ/2. At the third fret, m = 3, therefore L₃ = 3 × 0.58022 / 2, resulting in L₃ = 0.87033 m. For the fourth fret, m = 4, which gives L₄ = 4 × 0.54766 / 2, equating to L₄ = 1.09532 m. The distance between the two frets is Δd = L₄ – L₃, so Δd = 1.09532 - 0.87033, leading to Δd = 0.22499 m or 22.5 cm, rounded to 23 cm.
Conclusion:
The total net force acting on the objects is 16 N, directed towards the right.
Clarification:
It is stated that,
The force exerted by the dog,
(to the right)
The force exerted by Simone,
(backward)
Here, assume the backward direction is negative and the right direction is positive.
The net force will move in the direction where the larger force is present. The net force can be calculated as:


F = 16 N
Thus, the net force amounts to 16 N, acting towards the right.
Answer:

Explanation:
The beacon is rotating at an angular speed of

so we have



We know that

At this point we have


So we can conclude with


Answer:
The total energy saving achieved will be 0.8 KWH
Explanation:
It is provided that there are 50 long light bulbs rated at 100 W, thus the total power consumed by 50 bulbs equals 100×50 = 5000 W = 5 KW
Additionally, 30 bulbs are rated at 60 W
Consequently, the total power consumption of 30 bulbs is 30×60 = 1800 W = 1.8 KW
The cumulative power of all 80 bulbs is 1.8 + 5 = 6.8 KW
Considering the operation time of 3 hours
We know that energy 
Now, the power consumption per CFL bulb equals 25 W
Thus for 80 bulbs, power equals 80×25 = 2000 W = 2 KW
So the energy for 80 bulbs amounts to 2×3 = 6 KWH
Hence, the overall energy saving is 6.8 - 6 = 0.8 KWH