Answer:
Explanation:
The maximum velocity of an object moving in a curve beyond which it will slide off the curve is given by the relationship in equation (1);
where 
is the coefficient of friction between the object and the surface of the curve, g is acceleration due to gravity and r is the radius of the curve.
Given;
v = 0.8m/s
g = 
r = ?
In order to solve for , we can simply make it the subject of formula from equation (1) as follows;
since we were not given the value of r, we can just substitute other known values, then solve and leave the answer in terms of r.
Therefore;
From the law of Galileo Galilei :v²=v₀²+2ad we take the speed
v²=0+2*4.90*200=1960=>v=√1960=44.27 m/s
Answer:3.4 seconds
Explanation:
Initial velocity(u)=0
acceleration=34.5m/s^2
Height(h)=200m
Time =t
h=u x t - (gxt^2)/2
200=0xt+(34.5xt^2)/2
200=34.5t^2/2
Cross multiply
200x2=34.5t^2
400=34.5t^2
Divide both sides by 34.5
400/34.5=34.5t^2/34.5
11.59=t^2
t^2=11.59
Take them square root of both sides
t=√(11.59)
t=3.4 seconds
Answer:
You are exactly right. The molecules in hot air are moving faster than the molecules in cold air. Because of this, the molecules in hot air tend to be further apart on average, giving hot air a lower density. That means, for the same volume of air, hot air has fewer molecules and so it weighs less
