Answer:
Explanation:
(a)
In event A , one has to walk along diameter of the field from X to Y.
In this event , walk is along a straight line , both displacement and distance covered will be same.
Distance = displacement = 1 km.
option ii is correct .
(b )
radius of circular track r = 0.5 km
length of track = circumference = 2π r
= 2 x 3.14 x .5 = 3.14 km
Length of running in event B is 15.7 km
No of rounds = 15.7 / 3.14 = 5
option iii is correct .
( c )
speed = length of race / time
time = length of race / speed
= 15. 7 km / 3.14 km /h
= 5 hours .
option iv is correct option.
(d)
In event C , length of race is 25.12 km
speed = length of race / time taken
= 25.12 km / 4 hour
= 6.28 km/h .
Option i is correct.
Answer:
(a) (ii)
(b) (iv)
(c) (i)
(d) (i)
Explanation:
diameter, XY = 1 km
Event A- Fast walking along the diameter of the field.
Event B- A 15.7 km running race along the circular track.
Event C- A 25.12 km cycling race along the circular track.
(a) When athletes walked from X to Y , the distance is equal to the displacement which is equal to the diameter = 1 km.
Option (ii).
(b) distance = 15.7 km
distance traveled by one round = 3.14 x 1 = 3.14 km
So, the number of round complete in B = 1.57/3.14 = 0.5
option (iv).
(c)If Pihu ran at an average speed of 3.14 km/h during Event B, then she would finish the race in
time, t = 1.57/3.14 = 0.5 hours
option (i)
(d) What should the average speed of cyclist Yousef be, so that he can complete Event C in 4hours?
Distance = 25.12 km
time , t = 4 hours
Speed = 25.12 / 4 = 6.28 km/h
Option (i)
the atomic number of phosphorus is
Answer:
The atomic number of phosphorus is 15.
Explanation:
It’s found after Si(Silicon) and before S(sulphur)
Two boys X and Y each have the same total weight
and are standing on soft ground.
Which boy is more likely to sink into the soft ground and
why?
boy more
likely to sink
pressure on soft
ground
А
Х
larger than Y
B
Х
smaller than Y
C
Y
larger than X
D
Y
smaller than X
Answer:
the child with the smallest area will be the one who sinks
Explanation:
The child who will sink to the ground is the one who exerts the greatest pressure on the ground, even though the force, which in this case is equal to the weight, is equal.
Pressure is defined by
P = F / A
in this case the strength of the children is their weight
F = W
P = W / A
therefore the pressure changes are in the area of contact with the ground, the child with the smallest area will be the one who sinks
Does water exist on Mars? Explain your answer. Why didn't Jupiter become a star during the early.
Answer:
yes water was discovered in mars
the force between the earth and the body which is at a distance r from the center of the earth is F. What must be this distance for the force to be doubled.
Answer:
Explanation:
The gravitational force between the earth and another body is F = -GM_em/r^2 r where G = 6.67 times 10^-11 Nm^2/kg^2 is the gravitational constant, M_e = 5.97 times 10^24 kg is the mass of the earth, m is the mass of the other body, and r is the position vector of the second body with respect to the centre of the earth.
Density of an object can be found by calculating mass divided by volume. If two objects have the same mass, but one has a greater volume, the object with more volume is less dense. Does water’s density change when it is frozen?
Answer:
yes, the density of ice is less than the density of water. Ice floats on water.
Explanation:
HELP ASAP!!!
What size object (impactor) may create such a crater?
Answer:
I HOPE IT WILL HELP YOU.
:D
What is not one of the main uses of springs?
A. Bike suspension
B. The seasons
C. Clock making
D. Car suspension
Quick answer
Answer:
b. the seasons
Explanation:
A boy shoves his stuffed toy zebra down a frictionless chute. It starts at a height of 1.45 m above the bottom of the chute with an initial speed of 1.23 m/s . The toy animal emerges horizontally from the bottom of the chute and continues sliding along a horizontal surface with a coefficient of kinetic friction of 0.231 . How far from the bottom of the chute does the toy zebra come to rest? Assume g=9.81 m/s2 .
Answer:
The answer is "4.97 m".
Explanation:
[tex]u = 1.23\ \frac{m}{s}\\\\[/tex]
[tex]H= 1.45 \ m\\\\[/tex]
[tex]\mu = 0.231\\\\[/tex]
The law of conservation tells us that heat energy at the top with kinetic energy at the top equals kinetic energy at the base.
[tex]mgh+\frac{1}{2}mu^2=\frac{1}{2}mv^2\\\\2gh +u^2 =v^2\\\\v=\sqrt{u^2+2gh}[/tex]
[tex]v=\sqrt{(1.23\ \frac{m}{s})^2+2(9.81 \frac{m}{s^2}) +(1.45\ m)[/tex]
[tex]=\sqrt{1.5129+19.62 +1.45}\\\\=\sqrt{22.5829}\\\\=4.75\ \frac{m}{s}[/tex]
Friction force is given by the formula
[tex]f=-\mu mg \\\\ma= -\mu mg\\\\a=-\mu g\\\\[/tex]
[tex]= -(0.231) \ (9.81\ \frac{m}{s^2})\\\\=-2.26611 \ \frac{m}{s^2}[/tex]
Now by using an equation of motion as
[tex]v^2-u^2= 2as[/tex]
From the above the distance traveled is
[tex]S=\frac{v^2-u^2}{2a}[/tex]
[tex]S=\frac{(0)^2-(4.75\ \frac{m}{s})^2}{2(-2.26611\ \frac{m}{s^2})}\\\\[/tex]
[tex]=\frac{-(4.75\ \frac{m}{s})^2}{2(-2.26611\ \frac{m}{s^2})}\\\\=\frac{-22.5625}{-4.53222}\\\\=4.97[/tex]
In other words, the distance from the bottom of the chute to the point where the toy zebra comes to rest is [tex]s = 4.97\ m[/tex]
why does a stone sink and a ship float
Answer:
A stone is more dense than water and the air in draft of the boat is less dense than water.
The force exerted by the earth on a body is called ______of a body.
Answer:
The force exerted by the earth on a body is called gravitational of a body.
i think this is the answer
Answer:weight
Explanation:
What acceleration is produced on a mass of 200g, when a force of 10N is exerted on it?
Answer:
f=ma......10N=0.2a....=50m/s
Answer:
here,
force = mass× acceleration
10 = 0.2 kg × a
or, 10/0.2=a
or, a = 50km/h^2
is the required ans .
Saul is testing an installation and discovers a short circuit what’s causing this
A.high current
B.high voltage
C.low resistance
D.low voltage
Answer:
im pretty sure that it's (A.) High current
Explanation:
pf
not 100% sure, tho
Non-ideal behavior for a gas is most likely to be observed under conditions of a) high pressure and low temperature. b) high temperature and high pressure. c) high temperature and low pressure. d) standard temperature and pressure. e) low temperature and low pressure.
Answer:
high temperature and low pressure
Explanation:
Real gases have intermolecular forces of attraction between them hence they can be liquified. However, gases approach ideal behavior at high temperature and low pressure.
According to the kinetic theory of gases, gases molecules move at incredibly high speeds and exhibit no intermolecular interaction because the gas molecules are isolated from each other.
At high temperature and low pressure, gas molecules are found to possess maximum kinetic energy. They move with a very high velocity and have minimal intermolecular interaction between them in accordance with the proposition of the kinetic theory of gases.
can anyone help me with this one
Answer:
c) sin c /sin d
because light is moving from denser to shallower medium
b) refraction of light
Explanation:
What is one Pascal pressure? What is its unit?
Explanation:
the force acting perpendicularly on unit area of surface
unit=pascle .
A pressure of one Newton per square meter .. The SI unit of 1 Pascal pressure is 1 Newton per square metre .
Which nucleus completes the following equation?
Please ignore the answer I chose, it might be wrong
Answer:
D. [tex]^{39}_{18} Ar[/tex]
Explanation:
The given nuclear equation is the beta decay of chorine in which an electron, known as a beta particle, is given off from within the nucleus due to the breakdown of a neutron within the nucleus into a proton and a beta particle, such that the atomic number is increased by 1 from 17 to 18, which is the atomic number or argon, Ar, as follows;
[tex]^{39}_{17}Cl \ \rightarrow \ ^0_{-1} e + \ ^{39}_{18} Ar[/tex]
Wagonium-292 has a half-life of 1 hour. If you started with an 80 gram sample, how much Wagonium-292 will remain after 4 hours? A.) 10g B.) 40g C.) 160g D.) 5G
After 1 hour, 80 g decays to 40 g.
After another hour (total 2 hours), 40 g decays to 20 g.
After another hour (total 3), 20 g decays to 10 g.
After one more hour (total 4), 10 g decays to (D) 5 g.
The mass of earth 6*10^24kg and radius is 400kg Now find the value of acceleration due to gravity when a object is 3600km from the earth surface
S/REF No. Date If the load distance of a level is 20 cm and effort distance is 6ocm, calculate the amount of effort required to lift a load 200 N.
Please help me , I also have to show work on paper
Answer:
Choose B
Explanation:
Hope Can I help you
1. explain the procedure undertaken if you have to measure the density of the contents of a milk carton. 2. two objects have the same mass. How about the density of the two objects?
To calculate the density of a substance, its mass and volume has to be determined. So that:
i. For the milk in the carton, its mass and volume should be known.
ii. For the two objects given in the question, their individual masses and volumes have to be determined.
Density of a substance (ρ) is the rate of the mass (m) of the substance to its volume (V). It is measure in kg/[tex]m^{3}[/tex].
i.e ρ = [tex]\frac{m}{V}[/tex]
The density of a substance can be determined once the mass and its volume have been accurately measured.
1. How to measure the density of the contents of a milk carton.
a. Determine the mass of the milk carton with its content.
b. Determine the mass of the milk carton when empty.
c. Subtract the mass of the milk carton when empty from the mass of the carton with its content. This will give the mass of the milk in the carton.
d. Using a beaker, measure the volume of the milk.
e. Divide the mass of the milk by its volume to determine its density.
2. How to measure the densities of two objects of equal mass.
a. Fill an Eureka's can or a beaker with sprout with water to its brim.
b. Slowly drop the mass into the beaker with water so as to collect the volume of the liquid displaced into another beaker.
c. The volume of the liquid displaced is the volume of the mass.
d. Divide the mass of the object by its volume to determine its density.
NB: These procedures are observed to determine the densities of the two object individually.
For more explanations, visit: https://brainly.com/question/17924956
A merry-go-round rotates with a centripetal acceleration of 18 m/s^2. If the outer horses are 9 m from the center of the ride. What is their velocity?
A. 12.7 m/s
B. 14.6 m/s
C. 16.3 m/s
D. 10.4 m/s
Answer:
A
Explanation:
a_c = v^2/r
v = sqrt*a_c × r*
v = sqrt * 18 × 9*
v = 9×sqrt *2*
v = 12. 7 m/s
Annie has a soccer ball and a cake ball she kicks each ball with the same Force the soccer ball accelerates at 3 m per second squared and the kickball accelerates at 5 m per second squared use Newton's law to describe why the kickball has a greater acceleration
Give reason Pascal is a derived unit
The pascal is the SI derived unit of pressure used to quantify internal pressure, stress, Young's modulus and ultimate tensile strength.
Symbol ⇥ PaWhat is meant by the term wave front?
Explanation:
Wave front, imaginary surface representing corresponding points of a wave that vibrate in unison. ... Wave fronts for longitudinal and transverse waves may be surfaces of any configuration depending on the source, the medium, and the obstructions encountered.
Which of the following is a contact force?
A. applied
B. electromagnetic
C. nuclear
D. gravity
applied force is a contact force
10. Explain the principle of electric motor. Write its uses.
Explanation:
The principle of an electric motor is based on the current carrying conductor which produces magnetic field around it. A current carrying conductor is placed perpendicular to the magnetic field so that it experiences a force.
The largest electric motors are used for ship propulsion, pipeline compression and pumped-storage applications with ratings reaching 100 megawatts. Electric motors are found in industrial fans, blowers and pumps, machine tools, household appliances, power tools and disk drives.
What kind of circuit is the one shown below?
A. Series
B. Parallel
C. Open
D. Combination
That's a parallel circuit. (B)
When current from Point-A reaches the 3-way intersection just to the right of Point-B, it has to make a choice: Either turn left, go through B, and light the lower bulb, or go straight and light the upper bulb.
A circuit that has any "decision" points in it is a parallel circuit. What happens in the real world is: The current splits up. Some of the current that reaches the intersection turns left toward Point-B, and the rest of it goes straight up.
A series circuit is one in which there's only one possible path all the way around. There are no intersections of more than 2 roads, and no electron ever has to decide which way to flow.
An open circuit is one in which there's a break somewhere along the line and electrons can't jump across it. It's like a railroad where a big piece is cut out of the track somewhere. So no trains can travel on that route, and there's no current flowing anywhere in the circuit.
I'm not so sure about a "combination" circuit. I guess you could give that name to a complicated circuit that has some series parts and some parallel-parts. Personally, I'd call that a "series-parallel" circuit. But it really doesn't matter right now. Whatever the word means, the circuit in the picture is definitely not a "combination" circuit.
Answer:
B. Parallel Circuits
Explanation:
A parallel circuit is constructed by connecting the terminals of all the individual load devices so that the same value of voltage appears across each component. In a parallel circuit, charge divides up into separate branches such that there can be more current in one branch than there is in another.
hope i helped
Which type of wires (copper, aluminum, or string) are ferromagnetic metals?
Answer:
Copper isn't ferromagnetic,
Aluminum isn't ferromagnetic,
String has a ferromagnetic property
So in conclusion:
The answer is strings :)
A car generator turns at 400 rpm (revolutions per minute) when the engine is idling. It has a rectangular coil with 300 turns of dimensions 5.00 cm by 6.46 cm that rotates in an adjustable magnetic field. What is the field strength needed to produce a 24.0 V peak emf
Answer:
The field strength needed to produce a 24.0 V peak emf is 0.5913 T
Explanation:
From the formula for maximum emf of a generator,
[tex]emf_{max}= NAB\omega[/tex]
∴ [tex]B = \frac{emf_{max} }{NA\omega}[/tex]
Where N is the number of loops
A is cross section of loops
B is magnetic field strength
ω is the angular frequency of loops
From the question, [tex]emf_{max} = 24.0V[/tex]
N = 300 turns
A = l × b ( since it is a rectangular coil)
A = 6.46 cm × 5.00 cm
A = 0.0646 m × 0.05 m
A = 0.00323 m²
ω = 400 rpm = (400/60)×2π rad/s
ω = 41.8879 rad/s
Putting all the parameters into the formula
[tex]B = \frac{emf_{max} }{NA\omega}[/tex]
[tex]B = \frac{24.0}{300\times0.00323\times41.8879}[/tex]
[tex]B = 0.5913T[/tex]
Hence, the field strength needed to produce a 24.0 V peak emf is 0.5913 T
