Answer:
The hikers average speed due north is 0.2 km per minute.
Explanation:
Speed is the ratio of distance moved by a body to the time taken.
i.e speed = [tex]\frac{distance}{time}[/tex]
Since the hiker walks due north and due west, then his average speed due north can be determined by;
Average speed = [tex]\frac{total distance due north}{total time taken}[/tex]
Total distance due north = 5.0 + 7.0
= 12.0 km
Total time taken = 20 + 40
= 60 minutes
= 1 hour
Average speed due north= [tex]\frac{12}{60}[/tex]
= [tex]\frac{1}{5}[/tex]
= 0.2
Average speed due north = 0.2 km/minute
The hikers average speed due north is 0.2 km per minute.
what is the diffference between distance and displacement
Answer:
distance is how far away something has travelled from another object, while displacement is how far something is from the other object. Displacement is a vector quantity, unlike distance.
The work done by a machine is always less then the work done on a
machine because of
Answer:
because of Friction is always present.
Advantages of wave model
Explanation:
plzz if it helps you then plzz mark me brainliest
A simple pendulum has a period of 3.45 seconds. When the length of the pendulum is shortened by 1.0m,the period is 2.81 seconds, calculate (a) the original length of the pendulum (b) The value of acceleration due to gravity
Answer:
2.97 meters
9.85 m/s^2
Explanation:
Given that :
Period (T1) = 3.45 seconds
When length , l is shortened by 1m, period (T2) = 2.81 seconds
Using the relation :
T = 2π√l/g
g = acceleration due to gravity
T1 = 2π√L/g - - - - (1)
Period 2:
x = shortened length = 1m
T2 = 2π√L-x/g - - - (2)
Square both sides
T1² = (2π)² L/g - - - (3)
T2² = (2π)² L-x/g - - (4)
Divide 3 and 4
(T2/T1)² = (L-x) / L
(2.81/3.45)^2 = (L - 1) / L
0.6633984 = (L - 1) / L
0.6633984L = L - 1
0.6633984L - L = - 1
−0.336601L = - 1
L = 1 / 0.336601
L = 2.9708764
Length = 2.97 meters
Acceleration due to gravity :
g = L(2π/T1)^2
g = 2.97(2π / 3.45)^2
g = 2.97 * 3.3168172
g = 9.8509
g = 9.85 m/s^2
g
How does your brain know which direction a sound comes from ?
Answer:
Your brain is able to do this by comparing tiny differences in the way that sounds affect each ear. ... Signals from the ear travel along the auditory nerve to the brainstem, where each individual cell responds to a specific time difference and direction.
Explanation:
It's because of your ears.
Jeff throws a ball straight up. For which situation is the vertical velocity zero?
a. on the way up
b. at the top
c. on the way back down
d. none of the above
Answer:
b. at the top
Explanation:
At the top of the climb, the vertical velocity of Jeff's throw has a value of zero.
Vertical velocity in this instance is acting against the acceleration due to gravity.
At the top of the thrown, the force of the throw becomes zero and the velocity also becomes zero. As the body finds it way downward, it begins to fall freely. The fall is due to the acceleration due to gravity which is experienced by every object on earth.HELP ME ASAP PLZZ
Which of the following is not a measurement taken by a radiosonde?
a. atmospheric composition
b. atmospheric pressure
c. wind speed
d. wind direction
Answer:
A atmospheric composition
Which of these would be the most efficient means to transmit light pulses over long distances?
Answer: It’s fiber optics so B
Which statement explains what happened next? Positive feedback caused his pancreas to stop secreting insulin. Negative feedback caused his pancreas to stop secreting insulin. Negative feedback caused his pancreas to produce more insulin. Positive feedback caused his pancreas to produce more insulin.
Answer:
Negative feedback caused his pancreas to produce more insulin.
Explanation:
Positive feedback is a feedback that causes an increase of product as a result of change while negative feedback is a feedback that causes a decrease in product as a result.
Negative feedback mechanism can be shown in the body as the control of blood sugar. The blood sugar is the product to be controlled. When there is an increase in blood sugar, the nerves sense a change. This change leads to secretion of insulin by the pancreas until homeostasis and then the secretion stops.
Answer:
negative feedback cause his pancreas to stop secreting insulin.
Explanation:
14. A television has a cash price of $1299. It can be purchased on a Hire Purchase plan by
making a deposit of $500 plus 10 monthly payments of $95. What is the total monthly
installment.
a) S1450
b) S450
c) S1299
d) S950
The muscle cells of an elephant Zontain 62 chromosomes. How many
chromosomes are in an elephant egg cell?
Answer:
31
Explanation:
In meiosis each sex cell has half the half the number of chromosomes than the parent cell. 62/2=31
A 2-kg ball traveling eastward at 5 m/s hits a 5-kg ball moving at 1 m/s eastward. The 2-kg ball bounces west at 3.0 m/s. What is the speed of the 5kg ball?
Answer:
1.8 m/s
Explanation:
Step one:
given data
m1= 2kg
u1= 5m/s
m2= 5kg
u2= 1m/s
v1= 3m/s
From
m1u1+m2u2= m1v1+m2v2
substitute
2*5+5*1 = 2*3+5*v2
10+5= 6+5v2
15-6= 5v2
9= 5v2
divide both side by 5
v2= 9/5
v2= 1.8 m/s
As the hot gas from a space shuttle is released downward, what does this cause to happen?
A. The shuttle will explode.
B. Negligible force on the shuttle.
C. Downward force on the shuttle.
D. Upward force on the shuttle
Answer:
D. Upward force on the shuttle
Explanation:
The hot gas from space shuttles released downward causes an upward force on the shuttle and propels it up the more.
This hot gas is produced from super cooled oxygen and hydrogen tanks within the shuttle. The upward force on the shuttle allows the craft to escape the gravitational pull of the earth on the shuttle Special level of rapid acceleration must be attained for the shuttle to escape the earth pull.A 5.00 kg crate is on a 21.0° hill.
Using X-Y axes tilted down the
plane, what is the y-component
of the weight?
(Unit = N)
Answer:
17.56 N
Explanation:
Given that,
Mass of a crate, m = 5 kg
It is on a 21.0° hill
We need to find the y component of the weight.
y component = mgsinθ
Put all the values,
y-component = 5×9.8×sin(21)
= 49×sin(21)
= 17.56 N
So, the y-component of the weight is 17.56 N.
Answer:
-45.745
Explanation:
it is negative because it is downwards.
Which one of the following is correct? *
A. Average speed and average velocity are the same.
B. There is no difference between uniform motion and uniformly accelerated motion.
C. Acceleration is the rate of change of speed.
D. Uniformly accelerated motion is a motion with constant acceleration.
Answer:
uniform acceleration motion is a motion with constant acceleration.
What is the speed of a wave with a wavelength of 2 m and a frequency of 9 Hz?
Answer:
The speed of a wave would be 18 with a wavelength of 2 m and a frequency of 9 Hz.
A jet aircraft is traveling at 262 m/s in horizontal flight. The engine takes in air at a rate of 85.9 kg/s and burns fuel at a rate of 3.92 kg/s. The exhaust gases are ejected at 921 m/s relative to the aircraft. Find the thrust of the jet engine. Answer in units of N Find the delivered power. Answer in units of W.
Answer:
[tex]F_T=60132.52N[/tex]
[tex]P=15814852.76W[/tex]
Explanation:
From the question we are told that
Velocity of aircraft [tex]V=263m/s[/tex]
Engine air intake rate [tex]\triangle M_a=85.9kg/s[/tex]
Fuel burn rate [tex]\triangle M_f =3.92kg/s[/tex]
Velocity of exhaust gas [tex]V_e =921m/s[/tex]
Generally the Mass change rate of Rocket is mathematically given by
[tex]\triangle M = \triangle M_a+\triangle M_f[/tex]
[tex]\triangle M= 85.9+3.92[/tex]
[tex]\triangle M=89.82kg/s[/tex]
Generally the Trust of the rocket is given mathematically by
[tex]F_T=(\triangle M *V_e)-(dM_a/dt)*(V)[/tex]
[tex]F_T=(89.82 *921)-(85.9)*(263)[/tex]
[tex]F_T=60132.52N[/tex]
Generally the Rocket's delivered power is mathematically given by
Delivered power P
[tex]P=V*F_T[/tex]
[tex]P=263*60132.52N[/tex]
[tex]P=15814852.76W.[/tex]
what are 3 physical changes of plastic
Answer:
1. Size
2. Shape
3. Color
Explanation:
Sorry if this is no help
what is the kinetic energy of a 0.25kg ball rolling at a speed of 2.5m/s
Answer:
Explanation:
Kinetic Energy formula:
KE = [tex]\frac{1}{2}[/tex]mv²
m=mass
v=speed
Given:
m=0.25kg
v=2.5m/s
Plug the values in:
KE = 1/2(0.25kg)(2.5m/s)²
KE = 0.78125 J (Joules)
An 69-kg jogger is heading due east at a speed of 1.6 m/s. A 63-kg jogger is heading 14 ° north of east at a speed of 1.5 m/s. Find (a) the magnitude and (b) the direction of the sum of the momenta of the two joggers. Describe the direction as an angle with respect to due east.
Answer:
[tex]P=203.3819375kg.m/s\\P\approx203.4kg.m/s[/tex]
[tex]\theta=6.4541\textdegree North East\\\theta\approx6.5\textdegree North East[/tex]
Explanation:
From the question we are told that
Mass of first jogger [tex]M=69kg[/tex]
Speed[tex]v_1=1.6m/s[/tex]
Direction [tex]d= East[/tex]
Mass of 2nd jogger [tex]M=63kg[/tex]
Speed [tex]v_2=1.5m/s[/tex]
Direction [tex]d= 14\textdegree north[/tex]
Generally equation for momentum along the the horizontal is mathematically given as
[tex]P_x=m_1v_1 +m_2v_2cos\theta[/tex]
[tex]P_x=(69)*(1.6) +(63)*(1.5)cos14[/tex]
[tex]P_x=202.0929461kg.m/s[/tex]
Generally equation for momentum along the the vertical is mathematically given as
[tex]P_y=m_2v_2cos\theta[/tex]
[tex]P_x=22.86161913kgm/s[/tex]
a)Generally the magnitude of momentum is mathematically given by
[tex]P=\sqrt{(P_x)^2+(P_y)^2}[/tex]
[tex]P=\sqrt{(202.0929461)^2+(22.86161913)^2}[/tex]
[tex]P=\sqrt{41364.21249}[/tex]
[tex]P=203.3819375kg.m/s[/tex]
[tex]P\approx203.4kg.m/s[/tex]
b) Generally the angle [tex]\theta[/tex] is mathematically given by
[tex]\theta=tan^-^1\frac{py}{px} \\[/tex]
[tex]\theta=tan^-^1\frac{22.86161913}{202.0929461}[/tex]
[tex]\theta=tan^-^1(0.1131242805)[/tex]
[tex]\theta=6.4541\textdegree North East[/tex]
When one end of a metal bar is heated, the opposite end will eventually become hot. Which of the following processes transfers the heat through the bar?
Group of answer choices
condensation
radiation
convection
conduction
How much energy is required to completely boil away 225 kg of water?
Hv = 226,000 J/kg
Hf = 334,000 J/kg
Answer:
E = 50850[kJ]
Explanation:
To boil the water we must use the latent heat of vaporization. Also we need to multiply this value by the mass of the water.
[tex]E=m*H_{v}[/tex]
Where:
E = energy produced by heat [J]
m = mass = 225 [kg]
Hv = 226000 [J/kg]
[tex]E = 225*226000\\E = 50850000 [J]\\E=50850[kJ][/tex]
I really need your help, please help me. How do I solve for ke without even having mass
(b)Suggest with reasons,what must be added to the flask to keep the liquid hot.
____________________________________________________
(a) a thin layer of vacuum is provided between the two walls of flask, to minimise the heat loss by conduction , because for conduction medium (molecules) is required , but now medium is absent .
.(b) the two walls are silvered to minimise the heat loss by radiation , because a shiny surface is a bad absorber and bad emitter of radiation i.e. good reflector of heat , so prevents the heat exchange between content of flask and surrounding .
(c) the lid of flask is provided with a tight cork stopper to minimise the heat loss by convection , so that convection currents cannot go out .
(d) a plastic (or metal) case is provided with a flask , to protect the flask from physical damage
hope it helps! please mark me brainliest
thank you! have a good day ahead
if u follow me, I will follow u back!
Starting from rest, a sprinter reaches his top velocity in 3 seconds. He runs a distance of 24m in 3 seconds. What is his acceleration? (Assume his acceleration is uniform)
Answer:
[tex]a=5.34\ m/s^2[/tex]
Explanation:
Given that,
Initial velocity of a sprinter, u = 0
He runs a distance of 24m in 3 seconds.
We need to find his acceleration. Let a be his acceleration. Using second equation of kinematics to find it.
[tex]s=ut+\dfrac{1}{2}at^2\\\\24=0+\dfrac{1}{2}a(3)^2\\\\a=\dfrac{24\times 2}{9}\\\\a=5.34\ m/s^2[/tex]
So, the acceleration of the sprinter is [tex]5.34\ m/s^2[/tex].
The acceleration of the sprinter from rest to his top speed is 5.33m/s²,
Given the data in the question
Since the sprinter starts from rest,
Initial velocity; [tex]u = 0[/tex]Time taken; [tex]t = 3s[/tex]Distance covered; [tex]s = 24m[/tex]Acceleration; [tex]a = \ ?[/tex]
To determine the acceleration of the sprinter, we use the second equation of motion:
[tex]s = ut + \frac{1}{2}at^2[/tex]
Where s is distance covered, u is initial velocity, a is acceleration and t is time.
We substitute our given values into the equation
[tex]24m = [0 * 3s] + [\frac{1}{2} * a * (3s)^2]\\\\24m = \frac{1}{2} * a * 9s^2\\\\24m = a * 4.5s^2\\\\a = \frac{24m}{4.5s^2} \\\\a = 5.33m/s^2[/tex]
Therefore, the acceleration of the sprinter from rest to his top speed is 5.33m/s²
Learn more: https://brainly.com/question/18835025
substances found in the food that the body needs
Answer:
There are six major nutrients: Carbohydrates (CHO), Lipids (fats), Proteins, Vitamins, Minerals, Water.
Explanation:
A car battery provides a voltage of 12 V to a vehicle. If 32 A of
current are drawn on a hot summer evening when the air conditioning
and lights are running, what is the resistance provided by the
electrical elements of the car?
A. 44 Ohms
B. 20 Ohms
C. 2.6 Ohms
D. 0.375 Ohms
Answer:
The resistance provided by the electrical elements is;
D. 0.375 Ohms
Explanation:
The relationship between the voltage, V, current, I, and resistance, R of an electric circuit is given as follows;
V = I × R
The given parameters of the circuit are;
The voltage provided by the car battery, V = 12 V
The current drawn by the air conditioning and lights, I = 32 A
From, V = I × R, we have;
R = V/I
Therefore, by substituting the known values, we have;
R = 12 V/(32 A) = 0.375 Ohms
The resistance provided by the electrical elements, R = 0.375 Ohms
The speed of a sound wave traveling through air is 400 meters per second. The wavelength of the wave is 25 meters What is the
frequency of the wave?
Answer:
16Hz
Explanation:
Given parameters:
Speed of sound = 400m/s
Wavelength = 25m
Unknown:
Frequency of the wave = ?
Solution:
To solve this problem;
V = F ∧
V is the velocity
F is the frequency
∧ is the wavelength
400 = F x 25
F = 16Hz
Answer:
16 hertz... I got it right on study-island
Explanation:
why is the index of refraction important for achromatic lenses?
Answer:
Refractive index is a measure of how light propagates through a material. The higher the refractive index the slower the light travels, which causes a correspondingly increased change in the direction of the light within the material.
Explanation:
100 points!!!! Will mark brainliest!!!!!!!!
This child is in motion jumping on a trampoline. There are four forces that apply to this situation. Which are they?
Applied force
Normal force
Tension force
Friction force
Spring force
Air-Resistance force
Electrical force
Magnetic force
Gravitational force
Answer:
Normal Force, Applied force, Gravitational Force, Spring Force
Explanation:
Normal Force so that he does not fall into trampoline, spring because the trampoline spring down when the force goes down, then up putting force upwards, gravitation because of gravity, and applied because of jumping
Answer:
i told u my thing got deleted lol
Explanation: