Answer:
Uses of concave mirror:
Shaving mirrors.
Head mirrors.
Ophthalmoscope.
Astronomical telescopes.
Headlights.
Solar furnaces.
Uses of convex mirror:
Convex mirrors always form images that are upright, virtual, and smaller than the actual object. They are commonly used as rear and side view mirrors in cars and as security mirrors in public buildings because they allow you to see a wider view than flat or concave mirrors.
please give me full points.
maximum speed of cheetah is
speed of gazelle is given as
Now the relative speed of Cheetah with respect to Gazelle
now the relative distance between Cheetah and Gazelle is given initially as "d"
now the time taken by Cheetah to catch the Gazelle is given as
so by rearranging the terms we can say
so above is the relation between all given variable
–30 = 5(x + 1)
Answer:
-30=5(x+1) is -7
Explanation:
distribute flip subtract 5 from both sides divide both sides by 5
Answer:
a) car does not skid, b) car skids, c) v = 11.07 m / s
Explanation:
a) When the car around in a curve all force must be exerted by friction, write Newton's second Law
Y axis (vertical)
N - W = 0
N = W = mg
X axis (radial
F = m a
The acceleration is centripetal
a = v² / r
fr = μ N
Let's calculate the maximum friction force
fr = μ m g
fr = 0.70 2000 9.8
fr = 13720 N
Let's calculate the force necessary to take the curve
F = m v² / r
F = 2000 11²/25
F = 9680 N
When examining these two values we see that the maximum value of the friction force is greater than the force to stay in the curve, for which the car does not skid
b) The speed of the driver is v = 18m / s, let's calculate the force to stay in the curve
F = 2000 18²/25
F = 25920 N
This force is greater than the maximum friction force, so it is a skating car
c) The friction coefficient decreases to μ = 0.5
fr = m a
μ mg = m v² / r
v = √μ g r
v = √(0.50 9.8 25)
v = 11.07 m / s
This is the maximum speed
Answer:
It's impossible for an ideal heat engine to have non-zero power.
Explanation:
Option A is incomplete and so it's possible.
Option B is possible
Option D is related to the first lae and has nothing to do with the second law.
Hence, the correct option is C.
The ideal engine follows a reversible cycle albeit an infinitely slow one. If the work is being done at this infinitely slow rate, the power of such an engine is zero.
We can also stat the second law of thermodynamics in this manner;
It is impossible to construct a cyclical heat engine whose sole effect is the continuous transfer of heat energy from a colder object to a hotter one.
This statement is known as second form or Clausius statement of the second law.
Thus, it is possible to construct a machine in which a heat flow from a colder to a hotter object is accompanied by another process, such as work input.
According to the second law of thermodynamics, it is impossible for heat energy to flow from a colder body to a hotter body, for an ideal heat engine to have an efficiency of 99%, and for a physical process to yield more energy than what is put in.
According to the second law of thermodynamics, it is impossible for heat energy to flow from a colder body to a hotter body. This is because heat naturally flows from a region of higher temperature to a region of lower temperature. This principle is what allows us to effectively use heat for various purposes, such as in heat engines.
An ideal heat engine is a theoretical construct used to study the efficiency of engines. The second law of thermodynamics states that no heat engine can have an efficiency of 100%, so it is impossible for an ideal heat engine to have an efficiency of 99%. This is due to the losses in heat transfer and other thermodynamic processes.
The second law of thermodynamics also implies that in any physical process, the total energy cannot increase. It is impossible for a physical process to yield more energy than what is put in. This principle is central to understanding energy conservation and the limitations of energy conversion.
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Answer:
Coefficient of static friction = 1.84
Explanation:
Note:
Top speed = 60 mph
Acceleration of cheetah = 18 m/s²
Find:
Coefficient of static friction
Computation:
Acceleration due to gravity = 9.8 m/s²
Coefficient of static friction = Acceleration of cheetah / Acceleration due to gravity
Coefficient of static friction = 18 / 9.8
Coefficient of static friction = 1.84
A. 4N
C. 16N
B. 8N
D. 32 N
The force being exerted on the 16-kg cart is 32N.
The force being exerted on the 16-kg cart can be determined using Newton's second law of motion, which states that force is equal to mass multiplied by acceleration. In the given graph, the cart is accelerating at a rate of 2 m/s2. Therefore, the force can be calculated as:
force = mass x acceleration
force = 16 kg x 2 m/s2 = 32 N
The 16-kg cart experiences a force of 32N, determined by applying Newton's second law of motion. According to this law, force equals mass multiplied by acceleration. In this scenario, the cart accelerates at a rate of 2 m/s². Substituting the values into the equation, the force exerted on the cart can be calculated as 16 kg multiplied by 2 m/s², resulting in a force of 32 N. This fundamental principle in physics establishes a quantitative relationship between force, mass, and acceleration.
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Answer:
D
Explanation: