Answer:
a) Watt is a derived unit because it's not a “base unit.”
b) The atomic clock is suitable for measuring time because natural atomic oscillations happen at a higher frequency and as a result they are more stable.
c) There is fluctuation in time measured by a pendulum clock because the pendulum rod changes in length slightly with changes in temperature, causing changes in the rate of the clock. An increase in temperature causes the rod to expand, making the pendulum longer, so its period increases and the clock loses time.
D) The weight of an object is more at pole and less at equator of the earth because the distance of the pole is less than the distance of the equator from the centre of the earth.
e) The weight of an object on the moon is about one-sixth the weight it would have on the earth because the moon's gravitation force is determined by the mass and the size of the moon. Hence, the weight of an object on the moon is 1/6th its weight on the earth.
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.
While traveling north on an expressway, a car traveling 60 mph (miles per hour) slows down to 30 mph in 12 minutes due to traffic conditions
Answer:
acceleration = - 150 m/s^2
distance = 9 miles.
Explanation:
initial speed, u = 60 mph
time, t = 12minutes = 0.2 hour
final speed, v = 30 mph
Let the acceleration is a and the distance is s.
By the first equation of motion
v = u + at
30 = 60 + a x 0.2
a = - 150 m/s^2
Let the distance is s.
Use third equation of motion is
[tex]v^2 = u^2 + 2 a s \\\\30^2 = 60^2 + 2 \times 150\times s\\\\s = 9 miles[/tex]
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
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
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
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:
Wavelengths of incoming solar radiation are __________________ the wavelengths of reradiated heat. Which term best completes the sentence
Explanation:
Hydraulic Pressure-Control, On-Off Deluge Valve
FP-400Y-5DC
The BERMAD model 400Y-5DC is an elastomeric, hydraulic line pressure operated deluge valve, designed specifically for advanced fire protection systems and the latest industry standards. The 400Y-5DC is activated by a hydraulically operated relay valve, through which opening and closing of the valve can be controlled either with a remote hydraulic command or with a wet pilot line with closed fusible plugs. An integral pressure reducing pilot valve ensures a precise, stable, pre-set downstream water pressure. The optional valve position indicator can include a limit switch suitable for Fire & Gas monitoring systems. The 400Y-5DC is ideal for systems that combine a remote wet pilot line with a high pressure water supply.
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
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
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
A car's bumper is designed to withstand a 5.04-km/h (1.4-m/s) collision with an immovable object without damage to the body of the car. The bumper cushions the shock by absorbing the force over a distance. Calculate the magnitude of the average force on a bumper that collapses 0.255 m while bringing a 890-kg car to rest from an initial speed of 1.4 m/s.
Answer:
3420.39 N
Explanation:
Applying,
Fd = 1/2(mv²-mu²)................. Equation 1
Where F = force on the bumber, d = distance, m = mass of the car, v = final velocity, u = initial velocity.
make F the subject of the equation
F = (mv²-mu²)/2d............... Equation 2
From the question,
Given: m = 890 kg, v = 0 m/s (to rest), u = 1.4 m/s, d = 0.255 m
Substitute these values into equation 2
F = [(890×0²)-(890×1.4²)]/(2×0.255)
F = -1744.4/0.51
F = -3420.39 N
The negative sign denotes that the force in opposite direction to the motion of the car.
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]
please help.. i got it wrong on my last attempt
Answer:
The answer is C.
Explanation:
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.
Learn more about natural resources at;
https://brainly.com/question/24623157
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.
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.
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.
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
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
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..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.
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 marble is rolling across a smooth 1.2 m tall table at a velocity of 3 m/s. How far from the edge of the table does it land? (SHOW ALL OF YOUR WORK)
Answer:
S = 1/2 g t^2 where t is the time to fall 1.2 m
t = (2 S / g)^1/2 = (2 * 1.2 / 9.8) = .495 s
Sy = Vy T = 3 m/sec * .495 sec = 1.48 m distance from edge of table
(Rotational speed has no effect since table is smooth)
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
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 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
What is an electric fuse? What is the working principle of electric fuse?
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:
...
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
A. A
B. C
C. D
D. B
HELLLP GUYS!!!
Answer:
B
Explanation:
