Answer:
Average speed = 24 km/h
Explanation:
Let the distance be x.Given the following data;
Uniform speed A = 30 km/h
Uniform speed B = 20 km/h
To find the average speed;
Mathematically, the average speed of an object is given by the formula;
[tex] Average \; speed = \frac {total \; distance}{total \; time} [/tex] ..... equation 1
Total time = TA + TB
[tex] T_{A} = \frac {x}{30} [/tex]
[tex] T_{B} = \frac {x}{20} [/tex]
[tex] Total \; time = \frac {x}{30} + \frac {x}{20} [/tex]
[tex] Total \; time = \frac {5x}{60} [/tex]
Total distance = x + x
Total distance = 2x
Substituting the values into equation 1;
[tex] Average \; speed = \frac {2x}{\frac {5x}{60}} [/tex]
[tex] Average \; speed = \frac {2x*60}{5x} [/tex]
[tex] Average \; speed = \frac {120}{5} [/tex]
Average speed = 24 km/h
please help.. i got it wrong on my last attempt
Answer:
The answer is C.
Explanation:
A 4.0-kg meatball is moving to the right with a speed of 6.0 m/s directly toward a 2.0 kg meatball
which is at rest. The two meatballs collide and stick together. What is their velocity immediately after
the collision?
Answer:
Explanation:
The equation for this is the one for the Law of Momentum Conservation which says that the momentum before the collision of the balls has to be the same after the collision because momentum cannot be created or destroyed. For us in particular:
[tex][(m_1v_1+m_2v_2)]_b=[(m_1+m_2)v_{both}]_a[/tex] and filling in:
[(4.0)(6.0) + (2.0)(0)] = [(4.0 + 2.0)v] and
24 + 0 = 6.0v and
24 = 6.0v so
v = 4.0 m/s to the right
5. A person standing on a 50 m cliff throws a rock upward at 26.5 m/s. How long will it take for the rock to reach the ground? Hint: determine the final velocity first.
Answer:
53 seconds
Explanation:
26.5/50
0.53 seconds
It will take approximately 5.42 seconds for the rock to reach the ground from a 50 m cliff when thrown upward with an initial velocity of 26.5 m/s.
The time it takes for the rock to reach its highest point. We can use the equation:
Final velocity (v) = Initial velocity (u) + Acceleration (a) × Time (t)
0 = 26.5 - 9.8 × t
9.8 × t = 26.5
t = 26.5 ÷ 9.8
t = 2.71 seconds
Now, we double the time to account for the time it takes for the rock to reach its highest point and fall back down:
Total time = 2 × t
Total time ≈ 2 × 2.71
Total time = 5.42 seconds
Therefore, it will take approximately 5.42 seconds for the rock to reach the ground from a 50 m cliff when thrown upward with an initial velocity of 26.5 m/s.
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An object 2cm high is placed 3cm in front of a concave lens of focal length 2cm, find the magnification?
Answer:
0.4
Explanation:
A concave lens is a diverging lens, so it will always have a negative focal length. Image distance is always negative for a concave lens because it forms virtual images.
From the lens formula;
1/f = 1/u+ 1/v
- 1/2 = 1/3 - 1/v
1/v = 1/3 + 1/2
v= 6/5
v= 1.2 cm
Magnification = image distance/object distance
Magnification = 1.2cm/3cm
Magnification = 0.4
A ball tied on a string rotates in a circular path as shown above. The only forces acting on the ball at any point are the weight and of the string. What is the equation for the net centripetal force at point C?
Answer:
the third one T-W
Explanation:
the direction of the Tension and weight are opposite
Define standard 1 killogram
" standard 1 meter
" standard 1 second
Answer:
-standard 1 kg : Kilogram (kg), basic unit of mass in the metric system.
-standard 1 meter: The standard metre is the length of the path travelled by light in vaccum during a time interval of 1/299792458 of a second.
- standard 1 second : The second (abbreviation, s or sec) is the Standard International ( SI ) unit of time.
Explanation:
HOPE IT HELPS YOU !!
A spring attached to a mass is at rest in the initial position (not shown). The spring is compressed in position A and is then released, as shown in position B. Which equation describes conservation of energy in position A?
Answer:
Explanation:
When the spring is compressed, it is compressed to its amplitude (whereas equilibrium is the spring's natural length with no mass attached to it and displacement is the spring's reaction to a mass hung on the end of it without any "extra" pushing or pulling on the mass). It is at the amplitude where the spring experineces max potential energy, which is choice 2, E = mph
Answer:
its c
Explanation:
...
do you believe that the universe is expanding?
Answer:
Yes
Explanation:
Many scientists believe that the universe is expanding at an increasing rate. Scientists cannot explain how the universe is expanding at an increasing rate because by law of conservation of energy, there is only a finite amount of energy. Thus, scientists have called this new source of energy dark matter and it is all around the universe helping shape and form the universe.
find the x component of a vector of 105 km/h at an angle of 25 degrees.
Answer:
Explanation:
First I converted the km/h to m/s, which is the more common unit for velocity. In m/s, 105 km/h is 29.2. Thus, to find the x component of the vector:
29.2cos25 = 26 m/s
If you want it in km/h:
105cos25 = 95 km/h
A projectile is fired horizontally from a gun that is 58.0 m above flat ground, emerging from the gun with a speed of 170 m/s. (a) How long does the projectile remain in the air
Answer:
t = 3.44 s
Explanation:
We are given;
Fired from rest, and so; u = 0 m/s
Final speed; v = 170 m/s
Height above flat ground; y_o = 58 m
Height at starting point; y = 0 m
Thus, from Newton's equation of motion, we have;
y - y_o = ut - ½gt²
(since it's motion is against gravity)
Plugging in the relevant values, we have;
0 - 58 = 0 - (½ × 9.8 × t²)
-58 = -4.9t²
t² = 58/4.9
t = √(58/4.9)
t = 3.44 s
How do you calculate joules? someone please help me I beg
Answer:
Joules = Watts × SecondsExplanation:
If you multiply the number of watts by the number of seconds, you'll end up with joules.
The emf, formerly known as electromotive force, is actually... a potential difference. a field. a force. an energy.
Answer:
The correct option is (a) "potential difference".
Explanation:
EMF is an Electromotive force. It is the energy per unit electric charge that is imparted by an energy source, such as an electric generator or a battery. One of the terminals of device is positive and other is negative. It is also defined as terminal potential difference when no current flows.
It is actually a potential difference across the terminals.
Answer:
potential difference
Explanation:
why is fundamental unit called derived unit ?
Since fundamental units are elementary in nature and cannot be reduced further, so it can not be reduced further, so it cannot be expressed in other units
If the universe is infinite, then how come there are things disappearing from the horizon? I was at a point in this video (TRUE Limits Of Humanity from Kurzgesagt) about true limits of humanity, and the narrator mentioned that (04:12) "...there is a cosmological horizon around us. Everything beyond it, is traveling faster, relative to us, than the speed of light. So everything that passes the horizon is irretrievably out of reach forever and we will never be able to interact with it again." Are they talking about how galaxies passing the horizon are physically absent, or just visually aren't there and we are unable to interact with them?
Answer:
The big rip theory
Explanation:
I believe what you are referring to is the big rip theory, in which the universe expands faster than the speed of light Kurzgesagt refers to it as a "horizon" but in reality it's a little more complicated than that. Eventually the expansion of the universe will accelerate far beyond the speed of light creating space between molecules until eventually all matter is fleeting and the entire universe is an endlessly vast cosmic void with not but the occasion molecule left from a time when things weren't so lonely.
Two blocks, one of mass 5 kg and the other of mass 2 kg, are attached to opposite ends of a light string and hung vertically from a massless, frictionless pulley. Initially the heavier block is held in place a distance 2.5 m above the floor, the lighter block is just touching the floor, and the cord is taut. Then the heavier block is released and comes crashing to the floor while the cord slackens and the lighter block continues to rise. What is the maximum height reached by the lighter block
Answer:
[tex]H_{max}=3.4m[/tex]
Explanation:
From the question we are told that:
Mass 1 [tex]m_1=5kg[/tex]
Mass [tex]m_2=2kg[/tex]
Distance above floor [tex]d=2.5m[/tex]
Generally the equation for Conservation of energy is mathematically given by
[tex]0.5m_1v^2+0.5m_2v^2=2mg[/tex]
[tex]0.5m_1v^2+0.5m_2v^2=2g(m_1-m_2)[/tex]
[tex]v^2(0.5*m_1+0.5*m_2)=2*g(m_1-m_2)[/tex]
[tex]v^2(0.5*5+0.5*2) = 2 * 9.8 * (5 - 2)[/tex]
[tex]v^2=\frac{58.8}{3.5}[/tex]
[tex]v=4.1m/s[/tex]
Generally the equation for The maximum height of lighter block is mathematically given by
[tex]H_{max}=d+\frac{v^2}{2g}[/tex]
[tex]H_{max}=2.5+\frac{16.2}{2*9.81}[/tex]
[tex]H_{max}=3.4m[/tex]
A plane is flying a circular path at a speed of 55.0 m/ s, with a radius of 18.3 m. The centripetal force needed to maintain this motion is 3000 N. What is the plane's mass?
The plane has a centripetal acceleration a of
a = v ²/r
where v is the plane's tangential speed and r is the radius of the circle. By Newton's second law,
F = mv ²/r
Solve for the mass m :
m = Fr/v ² = (3000 N) (18.3 m) / (55.0 m/s)² ≈ 18.1 kg
show that pv=nrt has the same unit with energy
Answer:
It is proved.
Explanation:
PV = n R T
where, P is the pressure, V is the volume, n is the number of moles, R is the gas constant, T is the absolute temperature.
Unit of pressure is Pascal= Newton/square meter = [tex][ML^{-1}T^{-2}][/tex]
Unit of volume is cubic meter = [tex][L^{3}][/tex]
So, the unit of P V
[tex][ML^{-1}T^{-2}] \times [L^{3}]\\\\[ML^2T^{-2}}[/tex]
[tex][ML^{2}T^{-2}][/tex]
It is same as the unit of energy.
hence proved.
CLASS ENVIRONMENTAL SCIENCE
The____domain incorporates cultural norms that directly impact sustainable development. The___ domain focuses on the protection and preservation of natural and artificial resources
Blank 1: Blank 2:
A: social. A: public policy
B: economic. B: technological
C: sustainable. C: environmental
Which items did Mendeleev write down on note cards while he was observing
different elements?
A. Buoyancy
B. Density
C. Color
D. Atomic mass
Mendeleev wrote down atomic mass
Answer:
A. Buoyancy.
hope it helps
stay safe healthy and happy..Which describes an atom that has fewer neutrons than protons and more electrons than protons?
negative compound
positive compound
positive ion
negative ion
Answer:
Negative ion
.................
rainfall occurs on the earth due to effect of gravity
Answer:
TrueBecause Gravity is the force of attraction between two objects, and Earth's gravity pulls matter downward, toward its center. It pulls precipitation down from clouds and pulls water downhill. Gravity also moves air and ocean water. ... Gravity pulls denser air and water downward, forcing less dense air and water to move upward.Carryonlearning
A satellite of mass 5460 kg orbits the Earth and has a period of 6520 s
A)Determine the radius of its circular orbit.
B)Determine the magnitude of the Earth's gravitational force on the satellite.
C)Determine the altitude of the satellite.
Answer:
what if I do and b then someone else c I don't have enough time pls
In Boolean Algebra 1 represent
a)5V
b)1V
c)Both a&b
d)None of above
Answer:
hey hi mate
ur answer is move of above
hope you like it
plz mark it as brainliest
The large reservoir of comet nuclei far beyond Pluto, from which we believe new long-period comets come into the inner solar system, is called:
Answer:
Oort cloud
Explanation:
The large reservoir of comet nuclei far beyond Pluto, from which we believe new long-period comets come into the inner solar system, is called Oort cloud.
The comets hich have the large periods that means more than 200 years to orbit the Sun generaly comes from Oort cloud hich is also knon as the cometary cloud.
Which statement best describes how pigments affect what colors humans
see?
A. Pigments separate white light into different colors based on
wavelengths. Humans see colors within a certain range of
wavelengths.
B. Pigments emit light in different colors. Humans see the color that
a certain pigment emits.
C. Pigments reflect some wavelengths of visible light and absorb
others. Humans see the absorbed wavelengths.
D. Pigments reflect some wavelengths of visible light and absorb
others. Humans see the reflected wavelengths.
Answer:
C
Explanation:
Pigments reflect some wavelength of visible light and absorb
how much does a car weighr if each tyre cover of 4cm^2 and exert a pressure of 100000Nm^-2 on the ground it is physics questions
Answer:
Weight = 160 N
Explanation:
The weight of an object is a measure of the gravitational force on the object. So that weight is synonymous to the force applied by the object.
i.e Weight = mass x gravitational force
Also, the pressure of an object is the ratio of its force to area covered by the object. So that;
P = [tex]\frac{F}{A}[/tex]
Given that: area = 4 [tex]cm^{2}[/tex] (0.0004 [tex]m^{2}[/tex]), and pressure = 100 000 N[tex]m^{-2}[/tex].
Then;
F = PA
= 100 000 N[tex]m^{-2}[/tex] x 0.0004 [tex]m^{2}[/tex]
F = 40 N
The force applied on the ground by each of the four tyres of the car is 40 N.
Thus, the weight of the car = 4 x 40 N
= 160 N
What is an electric fuse? What is the working principle of electric fuse?
A. A
B. C
C. D
D. B
HELLLP GUYS!!!
Answer:
B
Explanation:
Question 9 of 10 The data table shows how the amplitude of a mechanical wave varies with the energy it carries. Analyze the data to identify the mathematical relationship between amplitude and energy. Use your equation to find the energy if the amplitude is 8 units. Amplitude Energy 1 unit 2 units 2 units 8 units 3 units 18 units 4 units 32 units
Answer:
A Em
1 ½ K
2 ½ k 4 = 2k
3 ½ k 9 = 4.5 k
4 ½ k 16 = 8k
Explanation:
The total mechanical energy of a simple harmonic movement is constant in time, let's look for the energy at one end of the movement, where the velocity of the body is zero.
Em = U = ½ k x²
at the end x = A
Em = ½ k A²
Let's build a table for the energy and as a function of the amplitudes of the movement
A Em
1 ½ K
2 ½ k 4 = 2k
3 ½ k 9 = 4.5 k
4 ½ k 16 = 8k
as a function of the lowest energy
1 Eo = ½ k
2 4Eo
3 9 Eo
4 16Eo
How does the construction of dams positively affect natural resources?
by providing water for irrigation and restoring trees to areas where forests once existed
by creating reservoirs, preventing flooding, and renewing destroyed ecosystems
by preventing flooding, creating reservoirs, and providing water for irrigation
by renewing destroyed ecosystems and restoring trees to areas where forest once existed
Other person is incorrect, I did the test on edg.
Answer:
A. by providing water for irrigation and restoring trees to areas where forests once existed
The construction of dams positively affect natural resources by providing water for irrigation.
What is natural resources?Natural resources serves as materials thst is found in nature which are used by humans. These natural substances are soil, water.
Therefore, building of dams can help irrigation by using water which is a natural resources.
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