Answer:
Explanation:
F = ma. For us, this looks like
60 = 30a and
a = 2 m/s/s
If the force goes up to, say, 90, then
90 = 30a and
a = 3...if the force goes up, the acceleration also goes up.
If the mass goes up to say, 60, and the force stays the same, then
60 = 60a and
a = 1...if the mass goes up, the acceleration goes down.
1. It’s true
4 ,7 ,8 is correct
Answer:
4°C
Explanation:
Water is densest at 4°C. Since dense water sinks, the bottom of the lake will be 4°C.
Answer:
The tangential velocity of a rotating object is:
v = r*w
where r is the radius, and w is the angular velocity.
w = 2*pi*f
where f is the frequency.
We know that the record plater does 11 revolutions in 20 seconds, then it does:
11 rev/20s = 0.55 rev/s = f
then we have:
w = 2*pi*0.55 s^-1 = 2*3.14*0.55 s^-1 = 3.454 s^-1
The radius of a record player is really variable, it is around 10 inches, so i will use r = 10in, which is the rotating part of the record player.
then the tangential velocity is:
v = 10in*3.454 s^-1 = 34.54 in/s