Answer:
The valves prevent the backward flow of blood. These valves are actual flaps that are located on each end of the two ventricles (lower chambers of the heart). They act as one-way inlets of blood on one side of a ventricle and one-way outlets of blood on the other side of a ventricle.
Explanation:
<span>Science is always defined as the body of knowledge and linked to something
related to the physical world, phenomena and lives of everything that exist on
Earth. Science is categorized in various ways. Pure, practical or theoretical, is the largest
distinction of science or whether
science is applied. Generally, pure
science is subdivided into Physical sciences, Earth sciences, and Life
sciences. Physical sciences deal with
energy and matter, Earth sciences explain Earth’s phenomena, to the solar
system where it belongs and its atmosphere. And finally, life sciences describe
internal processes of living organisms, its relationship to each other and to
its environment.</span>
Answer:
speed of current is 5 mile/hr
Explanation:
GIVEN DATA:
speed of motorboat = 15 miles/hr relative with water
let c is speed of current
15-c is speed of boat at upstream
15+c is speed of boat at downstream
we know that
travel time=distance/speed

150+10c+150-10c=1.5(15-c)(15+c)
300=1.5(225-c^2)
300=337.5-1.5c^2
200=225-c^2
c^2=25
c = 5
so speed of current is 5 mile/hr
Options A and D are correct. The strength of the force of friction depends on the objects' sizes and weights and the heat generated by the friction and the types of surfaces involved.
<h3 /><h3>What is the friction force?</h3>
It is a type of opposition force acting on the surface of the body that tries to oppose the motion of the body. its unit is Newton (N).
Mathematically, it is defined as the product of the coefficient of friction and normal reaction.
On resolving the given force and acceleration in the different components and balancing the equation gets. Components in the x-direction.
The strength of the force of friction depends on the two factors, as;
A. The objects' sizes and weights.
D. The heat generated by the friction and the types of surfaces involved.
Hence, options A and D are correct.
To learn more about the friction force, refer to the link;
brainly.com/question/1714663
#SPJ1
Archimedes principle states
that
F1 / A1 = F2 / A2
F2 = (A2 / A1) * F1
Also, formula for the force is
F = mg. Formula for the area of the cylinder is A = πr^2, therefore we get
F2 = (πr2^2 / πr1^2) * mg
Since the diameter of the
cylinders are 2 cm and 24 cm, r1 = 12 and r2 = 1.
Substituting the values to the
derived equation, we get
F2 = (π 1^2 / π 12^2) * 2400 * 9.8
F2 = 163.3333 N
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