Answer:
60 N
Explanation:
because when we double the 30N, we will get 60N as a force
Answer:
37.545 m/s
Explanation:
f' = Actual frequency of horn = 269 Hz
f = Observed frequency of horn = 290 Hz
v = Speed of sound in air = 343 m/s
= Speed of second train = 13.7 m/s
= Speed of first train
From Doppler effect we have
The speed of the first train is 37.545 m/s
From the freezing temperature up to about 4°C (39°F) the water CONTRACTS. That is, it becomes MORE dense. I think I read that water is the ONLY known substance whose solid phase floats in its liquid phase. That's why the cubes float in your soda and bergs float in the ocean. And if weren't so, then life on Earth would not be possible ! Oceans and lakes would freeze from the bottom up, ONE TIME, and then never thaw again.
Static electricity travels to the door knob because of the friction caused by the feet on the carpet. the friction traveled through the person, to their hand, and to the door knob because it is the best conductor.
Answer:
a) 12.8212 N
b) 12.642 N
Explanation:
Mass of bucket = m = 0.54 kg
Rate of filling with sand = 56.0 g/ sec = 0.056 kg/s
Speed of sand = 3.2 m/s
g= 9.8 m/sec2
<u>Condition (a);</u>
Mass of sand = Ms = 0.75 kg
So total mass becomes = bucket mass + sand mass = 0.54 +0.75=1.29 kg
== > total weight = 1.29 × 9.8 = 12.642 N
Now impact of sand = rate of filling × velocity = 0.056 × 3.2 = 0.1792 kg. m /sec2=0.1792 N
Scale reading is sum of impact of sand and weight force ;
i-e
scale reading = 12.642 N+0.1792 N = 12.8212 N
<u>Codition (b);</u>
bucket mass + sand mass = 0.54 +0.75=1.29 kg
==>weight = mg = 1.29 × 9.8 = 12.642 N (readily calculated above as well)
