Answer:
Explanation:
Half life = 5.6
no of half life in 15.78 years = 15.78 / 5.26
= 3 .
[tex]N = N_0(\frac{1}{2})^n[/tex]
N₀ is original mass , N is mass after n number of half lives.
Inserting the given data in the equation above
[tex]50 = N_0(\frac{1}{2})^3[/tex]
N₀ = 50 x 2³
= 400 gm .
original sample will contain 400 gms of sample.
The rigid beam is supported by the three suspender bars. bars ab and ef are made of aluminum and bar cd is made of steel. if each bar has a cross-sectional area of 450 mm2, determine the maximum value of p if the allowable stress is (σallow)st = 200 mpa for the steel and ( σallow)al = 150 mpa for the aluminum. est = 200 gpa and eal = 70 gpa.
Answer:
Pmax = 67.5 KN
Explanation:
We need to calculate the maximum allowable value of P for both aluminum and steel bars.
FOR STEEL BARS:
Since,
(σallow)st = (Pmax)st/A
where,
(σallow)st = maximum allowable stress of steel bar = 200 MPa = 2 x 10⁸ Pa
A = Cross-sectional area of steel bar = 450 mm² = 0.45 x 10⁻³ m²
(Pmax)st = Maximum allowable force for steel bar = ?
Therefore,
2 x 10⁸ Pa = (Pmax)st/0.45 x 10⁻³ m²
(Pmax)st = (2 x 10⁸ Pa)(0.45 x 10⁻³ m²)
(Pmax)st = 9 x 10⁴ N = 90 KN
FOR Aluminum BARS:
Since,
(σallow)al = (Pmax)al/A
where,
(σallow)al = maximum allowable stress of Al bar = 150 MPa = 1.5 x 10⁸ Pa
A = Cross-sectional area of Aluminum bar = 450 mm² = 0.45 x 10⁻³ m²
(Pmax)al = Maximum allowable force for Aluminum bar = ?
Therefore,
1.5 x 10⁸ Pa = (Pmax)al/0.45 x 10⁻³ m²
(Pmax)al = (1.5 x 10⁸ Pa)(0.45 x 10⁻³ m²)
(Pmax)al = 6.75 x 10⁴ N = 67.5 KN
Since,
(Pmax)al < (Pmax)st
Therefore,
The maximum allowable force will be:
Pmax = (Pmax)al
Pmax = 67.5 KN
Heat pumps move heat from __________ to __________ areas & REQUIRES energy. *
A. cold, hot
B. hot, cold
What is the electrical power when the current is 20 amps and the voltage is 15 volts? *
A. 35 watts
B. 1.33 watts
C. 300 watts
Work is a transfer of matter. *
A. True
B. False
At a grocery store, 20 fl oz of brand A vitamin
water is sold for $0.95. What is the unit price of
the vitamin water per ounce, to the nearest cents?
Answer:
0.05 cents per fl oz
Explanation:
0.95 divided by 20
0.0475 to the nearest cent 0.05
What has an ionised atom lost or gained?
Protons
Gamma Rays
Electrons
Neutrons
Answer:
Electrons
Explanation:
Ionised atoms loose and gain electrons.
hope it helps!
Which happens during the day at the beach?
A. The water is warmer than the land, and air sinks over the water
B. The water is cooler than the land, and air sinks over the water
C. The water is warmer than the land, and air rises over the water
D. The water is cooler than the land, and air rises over the water
Answer:
c
Explanation:
not sure i think heating beach
Select the correct answer.
The motion of a car on a position-time graph is represented with a horizontal line. What does this indicate about the car's motion?
А.
It's not moving
B.
It's moving at a constant speed.
It's moving at a constant velocity
D. It's speeding up.
Answer:
a
Explanation:
Answer:
its a because its the only thing not moving
Explanation:
What are the three types of sea ice and why is each important?
Answer: New Ice, Nilas, and young ice.
Explanation:
New ice is recently frozen sea water that does not yet make up solid ice.
Nilas is an ice that bends without breaking around waves and swells.
Young ice is a transition stage between nilas and first-year ice.
30
. Which of the following represents the
statement "The difference of two square
numbers is positive
Answer:
In mathematics, the difference of two squares is a squared (multiplied by itself) number subtracted from another squared number. Every difference of squares may be factored according to the identity. in elementary algebra.
Explanation:
A 1200 kg car accelerates from 13m/s to 17m/s. find the change in momentum of the car?
Answer:
4800
Explanation:
The change in velocity of the car is 17-13=4m/s. Since the change in momentum is the mass multiplied by the change in velocity, the answer is 4*1200=4800. Hope this helps!
Given:
Mass,
m = 1200 kgChange in velocity,
Δv = 17-13= 4 m/s
Now,
The change in momentum is:
= [tex]Mass\times Change \ in \ velocity[/tex]
= [tex]1200\times 4[/tex]
= [tex]4800[/tex]
Thus the above answer is correct.
Learn more about momentum here:
https://brainly.com/question/8644950
A circuit has a current of 3 A. How many coulombs of charge will pass by a point in the circuit in 2 seconds?
- 6C
- 5C
- 3/2 C
- 2/3 C
One of these are the answer..
6C
Explanation:
The quantity of charge, Q, passing through an electric circuit is dependent on the electric current, I, and the time taken, t, for the current to flow. It is given mathematically as follows
Q = I x t ------------------------------(i)
Where;
I is measured in Amperes(A)
t is measured in seconds (s)
Q is measure in coulombs (C)
From the question,
I = 3A
t = 2s
Substitute these values into equation (i) as follows;
Q = 3 x 2
Q = 6C
Therefore, the number of coulombs of charge that will pass is 6C
Examples of pure substances are elements and _________.
A. Mixtures
B. Compounds
Answer:
b
Explanation:
Answer:
b
Explanation:
trust
A skier reaches the end of a 0.9 km track in 1.5 hours, at what speed does it travel?
(Please help,I need the answer as soon as possible)
Speed = Distance/Time
S = D/T
D = 0.9Km, T = 1.5hours,
S = 0.9/1.5
S = 0.6 m/s
hope it helps!
Answer: Speed =
distance = 0.9 * 1000 = 900 metres, because speed is measured in m/s so the km has to be converted to m
time = 1.5 * 60 = 90 seconds , because speed is measured in m/s so the time in minutes(m) has to be converted to seconds(s)
Speed =
= 10m/s
Read more on Brainly.com - https://brainly.com/question/11367821#readmore
Explanation: I don't know what this is but this is what I found and I hope it's helpful
This diagram shows a baseball’s motion. Which statement is best supported by the diagram?
a
Maximum Gravitational potential energy is at point R.
b
Kinetic energy becomes potential energy between points P and Q.
c
Kinetic energy becomes potential energy between points R and S.
d
Maximum kinetic energy is at point R.
Answer:
A
Explanation:
maximum gravitional potential energy is at point R
On a sky coaster (human pendulum) that reaches 20 meters from it's equilibrium position, a man of 70 kg is able to reach a maximum speed of
Answer:
Explanation:
Using the principle of conservation of energy, the potential energy is converted to kinetic energy, assuming any losses.
Kinetic energy is given by ½mv²
Potential energy is given by mgh
Where m is the mass, v is the velocity, g is acceleration due to gravity and h is the height.
Equating kinetic energy to be equal to potential energy then
½mv²=mgh
V
Making v the subject of the formula
v=√(2gh)
Substituting 9.81 m/s² for g and 20 m for h then
v=√(2*9.81*20)=19.799 m/s
Rounding off, v is approximately 20 m/s
Answer:
19.8 m/s
Explanation:
During the motion of a pemdulum bob, it casually converts kinetic energy to potential energy and vice versa.
A pendulum bob reaches its maximum speed at a position closest to its equilibrium position and has its lowest when it is farthest from the equilibrium position.
The maximum speed of a pendulum bob based on the mass involved and the maximum displacement from the equilibrium position is obtained from
Maximum kinetic energy = Maximum potential energy
Maximum potential energy occurs at the farthest point from equilibrium, that is,
P.E(max) = mgh
Maximum kinetic energy = ½mv²
½mv² = mgh
v = √2gh
g = acceleration due to gravity = 9.8 m/s²
h = farthest height from equilibrium position = 20 m
v = √(2×9.8×20) = 19.8 m/s
Hope this Helps!!!
explain nuclear fusion briefly
Answer:
Nuclear fusion is the process in which two atomic nuclei are fused together into a larger single nucleus, releasing energy in the process. ... In proton-proton fusion, four hydrogen atoms are fused into a single helium-4 atom, releasing a lot of energy in the process.
Explanation:
A starter pistol is fired 150m away from the spectators who hear the gun 0.5s after they see it fired. How fast does sound travel?
(Please help!)
Answer:
300m/s
Explanation:
speed = distance/time
150/0.5
What type of phase change occurs when water vapor in the atmosphere changes to liquid water in clouds?
Answer:
condensation, the process of changing from a gas to a liquid
Un semáforo de 80N cuelga del punto medio de un cable de 30m tendido entre 2 postes. Halle la tensión en cada segmento del cable si éste tiene un pandeo que lo hace descender una distancia vertical de 1m
Answer:
T1 = T2 = 602.33 N
Explanation:
I attached an image of the forces diagram below.
The x component of the forces for this cases is:
[tex]\Sigma F_x=T_1cos\theta-T_2cos\theta=0\\\\T_1cos\theta=T_2cos\theta\\\\T_1=T_2[/tex]
And the y components:
[tex]\Sigma F_y=T_1sin\theta+T_2sin\theta-W=0\\\\T_1=T_2=T\\\\\Sigma F_y=2Tsin\theta=W\\\\T=\frac{W}{2sin\theta}[/tex]
The angle is calculated by using the information about the length of the cable and the vertical distance of the traffic light:
[tex]\theta=tan^{-1}(\frac{1}{15})=3.81\°[/tex]
Thus, you obtain:
[tex]T=\frac{80N}{2(sin3.81\°)}=601.33N[/tex]
hence, the tension in both segments of the cable is 602.33 N
Adam observed properties of four different waves and recorded observations about the frequency and volume of each one in his chart. Which statement could Adam declare based on the data in the table
Se tienen 2 vectores cuyos módulos están en la misma razón que 5 y 2. Si cuando forman 53º su resultante mide 3√29u, ¿Cuánto mide el mayor vector?
Answer:
|v2| = 3.27
Explanation:
You have two vector v1 and v2. The relation between the magnitudes of both vectors is given by:
[tex]\frac{|v_1|}{|v_2|}=\frac{5}{2}[/tex]
Furthermore, the projection (the dot product) of one vector on the other one is given by the following formula:
[tex]v_1 \cdot v_2 = |v_1||v_2|cos\theta[/tex]
The dot product between v1 and v2 is 3√29. If you multiply the right hand side of the last equation by |v2|/|v2| you obtain:
[tex]3\sqrt{29}=\frac{|v_1|}{|v_2|}|v_2|^2cos(53\°)[/tex]
you do |v2| the subject of the formula:
[tex]|v_2|=\sqrt{\frac{|v_2|}{|v_1|}\frac{3\sqrt{29}}{cos53\°}}\\\\|v_2|=\sqrt{\frac{2}{5}\frac{3\sqrt{29}}{cos53\°}}=3.27[/tex]
Is jump rope a sport.
Answer:
yes
Explanation:
can someone tell me the answer for both of these pleaseeee i need it asap!!! i will give brainlist!!
Answer:
1/ decreases
2/ yes;
In general there is no relationship, and any combinations of frequencies and amplitudes are allowed.
Explanation:
Explanation for 1/ - please see the picture attached below
A pendulum is swinging back and forth with a period of 2.0 seconds here on Earth. This pendulum is then brought to the Moon, where the acceleration due to gravity is much smaller. What will happen to the period of the pendulum, assuming everything else about it (mass, length, initial swing height, etc) remains exactly the same
Answer: The period will be larger, with T = 4.92 seconds
Explanation:
The period of a pendulum can be obtained by the equation
T = 2*pi*√(L/g)
Where pi = 3.14, L = lenght of the pendulum and g = gravity acceleration.
You can see that the gravitational acceleration is on the denominator, this means that if we decrease the value of g, then the value of T will increase.
In Earth we have that:
2s = 2*3.14*√(L/9.8m/s^2)
L = (1/3.14)^2*9.8 m = 1m
In the moon we have g = 1.62 m/s^2
then the period in the moon is:
T = 2*3.14√(1/1.62) = 4.92s
A car takes 15 minutes to travel along a road that is 20 km long.
What is the average speed of the car?
A. 75 km/h B. 5.0 km/h C. 80 km/h D. 300 km/h
Answer:
C
Explanation:
15. 20
x4. x4
60. 80
80km/h
Answer:
80km/h
Explanation:
solution
given
d=20km
t=15min/60min=0.25h
s=?
s=d/t
s=20km/0.25h
s=80km/h
When a feather and coin are dropped towards the surface of the earth , do they reach ground together
Answer:
The coin will reach the ground first.
Explanation:
Because feather's mass is very low in comparison to a coin and due to air present in earth's atmosphere it will come down slowly.
hope it helps!
Answer:
The coin
Explanation:
Because the coin is heavier than the feather
The passage helps the reader to draw conclusions about which character's perspective? ºAlec ºAlice ºAlec's father ºAlec's mother
Answer:
I think it might be A: Alec but tell me if I'm wrong
Explanation:
Answer:
a
Explanation:
i did it on e d g e n u i t y
Choose the best definition for velocity
1. How fast something is going
2. Speed in a certain direction
3. Which direction something is going
4. Something speeding up
Which energy output objects work with the turbine?
What is motion ,terms used to measure motion ,examples etc
Answer:
A physic term
Explanation:
Answer:
Cambio de lugar o de posición de un cuerpo en el espacio.
Explanation:
mix 4 L of 30°C water is 6 L of 40°C water and you’ll have water at what temperature?
Answer:
dont know
Explanation:
need points
