Answer:
True
Explanation:
The image produced a convex mirror is always virtual irrespective of location. The size of the image is always smaller than the object. In a plane mirror the distance of the object and the distance of the image is same. But in a convex the image distance is always less than the object distance.
So, this statement is true.
D) Sound travels better through the compact molecules of air inside the balloon than the less compact molecules on the outside.
<span>3.92 m/s^2
Assuming that the local gravitational acceleration is 9.8 m/s^2, then the maximum acceleration that the truck can have is the coefficient of static friction multiplied by the local gravitational acceleration, so
0.4 * 9.8 m/s^2 = 3.92 m/s^2
If you want the more complicated answer, the normal force that the crate exerts is it's mass times the local gravitational acceleration, so
20.0 kg * 9.8 m/s^2 = 196 kg*m/s^2 = 196 N
Multiply by the coefficient of static friction, giving
196 N * 0.4 = 78.4 N
So we need to apply 78.4 N of force to start the crate moving. Let's divide by the crate's mass
78.4 N / 20.0 kg
= 78.4 kg*m/s^2 / 20.0 kg
= 3.92 m/s^2
And you get the same result.</span>
a) Making h as the shorter cathetus, we have,

We proceed to calculate the work done by gravity


b) It's necessary to calculate the Kinetic Energy, we use the equation of KE,


c) By work energy theorem

d) we calculate net work through the law of conservation



Answer:
<em>The object with the twice the area of the other object, will have the larger drag coefficient.</em>
<em></em>
Explanation:
The equation for drag force is given as

where
IS the drag force on the object
p = density of the fluid through which the object moves
u = relative velocity of the object through the fluid
p = density of the fluid
= coefficient of drag
A = area of the object
Note that
is a dimensionless coefficient related to the object's geometry and taking into account both skin friction and form drag. The most interesting things is that it is dependent on the linear dimension, which means that it will vary directly with the change in diameter of the fluid
The above equation can also be broken down as
∝
A
where
is the pressure exerted by the fluid on the area A
Also note that
= 
which also clarifies that the drag force is approximately proportional to the abject's area.
<em>In this case, the object with the twice the area of the other object, will have the larger drag coefficient.</em>