<u>Answer:</u>
Cheryl, Heather and Keaton all are correct.
<u>Explanation:</u>
Everything around you is made of matter and matter is anything that has mass and occupies space or in other words, anything which has volume is called matter.
Here, in the given example, Cheryl, Heather and Keaton all are correct because the mug, the hot chocolate which is inside the mug and the steam coming out of it, all have mass. Therefore, all are correct except for Mikayla.
Explanation:
In physical sciences, mechanical energy is the sum of potential energy and kinetic energy. It is the macroscopic energy associated with a system. The principle of conservation of mechanical energy states that if an isolated system is subject only to conservative forces, then the mechanical energy is constant. If an object moves in the opposite direction of a conservative net force, the potential energy will increase; and if the speed (not the velocity) of the object changes, the kinetic energy of the object also changes. In all real systems, however, nonconservative forces, such as frictional forces, will be present, but if they are of negligible magnitude, the mechanical energy changes little and its conservation is a useful approximation. In elastic collisions, the kinetic energy is conserved, but in inelastic collisions some mechanical energy may be converted into thermal energy. The equivalence between lost mechanical energy (dissipation) and an increase in temperature was discovered by James Prescott Joule.
Sound is an example of a mechanical wave. Mechanical waves are the kinds of waves that cannot be propagated without a medium. As such, these waves cannot travel through a vacuum, just like how sound cannot travel through space, since space is a vacuum.
Answer:
The value of the distance is 
.
Explanation:
The velocity of a particle(v) executing SHM is
where, 
is the angular frequency, 
is the amplitude of the oscillation and 
is the displacement of the particle at any instant of time.
The velocity of the particle will be maximum when the particle will cross its equilibrium position, i.e., 
.
The maximum velocity(
) is
Divide equation (1) by equation(2).
Given, 
and 
. Substitute these values in equation (3).
Answer:
3.9 m/s
Explanation:
We are given that
Mass of car,m=
Initial velocity,u=0
Distance,s=5.9 m
Average friction force,f=
We have to find the speed of the car at the bottom of the driveway.
Net force,
Where 
Acceleration,
v=3.9 m/s
