Answer
Maximum speed at 75 m radius will be 22.625 m /sec
Explanation:
We have given radius of the curve r = 150 m
Maximum speed
Coefficient of friction
Now new radius r = 75 m
So maximum speed at new radius
a) Remember Newton's second Law:
F = m*a
This means that the forces that is being exerted over an object is equal to the mass of the object times the acceleration that it has.
In this case, in order to hold the mass you need a force with the same magnitude but opposite direction to the gravitational force. The magnitude of this force would be the mass of the object times the gravitactional acceleration:
F = 2kg*9.80665m/s² = 19.6133 N
b) Using again Newton's second Law, we can issolate mass from that equation:
m = F/a
Then, the mass that a force of 1N can support is equal to:
m = 1N/9.80665m/s² = 0.102 kg
Answer:
Distance = 16.9 m
Explanation:
We are given;
Power; P = 70 W
Intensity; I = 0.0195 W/m²
Now, for a spherical sound wave, the intensity in the radial direction is expressed as a function of distance r from the center of the sphere and is given by the expression;
I = Power/Unit area = P/(4πr²)
where;
P is the sound power
r is the distance.
Thus;
Making r the subject, we have;
r² = P/4πI
r = √(P/4πI)
r = √(70/(4π*0.0195))
r = √285.6627
r = 16.9 m
Answer:
Explanation:
When the cold milk is added into the hot coffee, heat is transferred from the coffee (higher temperature) to the milk (lower temperature), until the two substances are at the same temperature (thermal equilibrium).
Therefore, the heat given off by the coffee is equal to the heat absorbed by the milk; so, we can write:
where:
is the mass of coffee
is the specific heat capacity of coffee
is the initial temperature of the coffee
is the mass of milk
is the specific heat capacity of milk
is the initial temperature of milk
is the temperature at equilibrium
Solving for , we find the final temperature of the coffee at equilibrium: