Density is mass per unit volume
remember
p= m/v where v is vol, m is mass and p is density
If the echo (the reflected sound) reaches your ear less than about
0.1 second after the original sound, your brain doesn't separate them,
and you're not aware of the echo even though it's there.
If the echo comes from, say, a wall, 0.1 second means you'd have to be
about 17 meters away from the wall. If you're closer than that, then the
echo reaches you in less than 0.1 second and you're not aware of it.
A. 30 meters . . .
No. You hear that echo easily
B. you're standing within range of both sounds . . .
No. You hear that echo easily, if you're at least 17 meters from the wall.
C. less than 0.1 second later . . .
That's it. The echo is there but your brain doesn't know it.
D. 21.5 meters
No. You hear that echo easily.
The the object that has the less mass will travel faster because let’s say for example the first object has the mass of M and the second object has the mass of 2M and if the momentum is equal so that means that we could divide M with M and we would get V1=2V2 (being V1 the velocity of the first mass and V2 the velocity of the second one) I hope I helped you out.
Answer:
(35 N - 10 N)/8kg = 3.125 m/s^2
Explanation:
The formula for Force is:
Force = Mass*Acceleration
(Force is equal to Mass times Acceleration)
Since we're told to find the acceleration of the box. We make acceleration the subject of the equation:
Acceleration = Force/Mass
(Acceleration equal to Force divided by Mass)
We know that the force are 35 N forward and 10 N backward, and the weight of the box is 8kg.
= (35 N - 10 N)/8kg
The reason that 35 N minus 10 N is because the 10 N is pushing the box backward.
= 25 N/8kg
= 3.125 m/s^2
Hope it helps :DD
