Hi there!
To find the appropriate force needed to keep the block moving at a constant speed, we must use the dynamic friction force since the block would be in motion.
Recall:

The normal force of an object on an inclined plane is equivalent to the vertical component of its weight vector. However, the horizontal force applied contains a vertical component that contributes to this normal force.

We can plug in the known values to solve for one part of the normal force:
N = (1)(9.8)(cos30) + F(.5) = 8.49 + .5F
Now, we can plug this into the equation for the dynamic friction force:
Fd= (0.2)(8.49 + .5F) = 1.697 N + .1F
For a block to move with constant speed, the summation of forces must be equivalent to 0 N.
If a HORIZONTAL force is applied to the block, its horizontal component must be EQUIVALENT to the friction force. (∑F = 0 N). Thus:
Fcosθ = 1.697 + .1F
Solve for F:
Fcos(30) - .1F = 1.697
F(cos(30) - .1) = 1.697
F = 2.216 N
Răspuns:
7: 4
Explicaţie:
Formula pentru calcularea cantității de căldură absorbită este exprimată ca;
Q = mc∆t
m este masa substanței
c este capacitatea termică specifică
∆t este schimbarea temperaturii
Conform legii calorimetriei, căldura pierdută de substanța rece = căldura câștigată de substanța fierbinte.
Folosind formula
(mc∆t) rece = (mc∆t) fierbinte
McCw∆tc = MhCw∆th
Deoarece au aceeași capacitate de căldură specifică, se vor anula. Ecuația devine;
Mc∆tc = Mh∆th ...... 1
Pentru apa rece;
∆tc = 45 ° C - 10 ° C
∆tc = 35 ° C
Pentru apa fierbinte:
∆th = 65 ° C - 45 ° C
∆th = 20 ° C
Înlocuiți în ecuația 1;
Mc (35) = Mh (20)
35Mc = 20Mh
Luând raportul dintre masa apei reci și cea fierbinte:
Mh / Mc = 35/20
Mh / Mc = 7/4
Prin urmare, lichidul trebuie amestecat împreună în raportul 7: 4
;Net force = mass of the body × acceleration of the body due to the net force
; 5000 = 2500 a...then divide both sides by 2500
; acceleration(a) = 2 m/s^2
Answer:
v = 8.4 m/s
Explanation:
The question ays, "A longitudinal wave has a frequency of 200 Hz and a wavelength of 4.2m. What is the speed of the wave?".
Frequency of a wave, f = 200 Hz
Wavelength = 4.2 cm = 0.042 m
We need to find the speed of the wave. The formula for the speed of a wave is given by :

So, the speed of the wave is equal to 8.4 m/s.
You would probably have a low frequency due to how much the wavelength is spread out.