I was having trouble with this problem, and problems like it: A 3.2 kg pelican, with a 1.73 kg fish in its mouth, is flying 1.52 m/s at a height of 40 m when the fish wiggles free and fall back toward the ocean. How fast is the fish moving when it hits the water?
Answer:
28.1 m/s
Explanation:
[tex]u_x[/tex] = Initial velocity of the fish = 1.52 m/s
y = Height of the bird = 40 m
[tex]a_y[/tex] = Acceleration in y axis = [tex]9.81\ \text{m/s}^2[/tex]
[tex]u_y[/tex] = Initial velocity in y axis = 0
[tex]y=u_yt+\dfrac{1}{2}a_yt^2\\\Rightarrow 40=0+\dfrac{1}{2}\times 9.81t^2\\\Rightarrow t=\sqrt{\dfrac{40\times 2}{9.81}}\\\Rightarrow t=2.86\ \text{s}[/tex]
[tex]v_y=u_y+a_yt\\\Rightarrow v_y=0+9.81\times 2.86\\\Rightarrow v_y=28.057\ \text{m/s}[/tex]
The final velocity in x direction will remain the same as the initial velocity as there is no acceleration in the x direction [tex]u_x=v_x=1.52\ \text{m/s}[/tex]
Resultant velocity is given by
[tex]v=\sqrt{v_x^2+v_y^2}\\\Rightarrow v=\sqrt{1.52^2+28.057^2}\\\Rightarrow v=28.1\ \text{m/s}[/tex]
The fish is moving at a velocity of 28.1 m/s when it hits the water.
A ball is thrown with 50J of kinetic energy, it hits a target which moves with 30J of kinetic energy, how much energy goes to the thermal store of the surroundings?
Answer:
The energy that will go will for thermal store of the surroundings is 20 J.
Explanation:
Given;
kinetic of the thrown ball, K.E₁ = 50 J
kinetic energy used to move the target, K.E₂ = 30 J
The excess energy that will go will for thermal store of the surroundings;
ΔK.E = K.E₁ - K.E₂
ΔK.E = 50J - 30J
ΔK.E = 20 J
Therefore, the energy that will go will for thermal store of the surroundings is 20 J.
3. A bee flies forward at 4.9 for 33 s, lands on a flower and stays there for 7s, then flies back along its previous route at 1.9 for 39 s. What is the average speed of the bee
during the entire time?
O 1.701
O 3.001
O 4.466
O 3.801
None of these is correct.
Answer:
None of these is correct.
Explanation:
The average speed can be derived from the sum of the total distance traveled and the total time taken.
Total distance = 4.9 + 1.9 = 6.8
Total time taken = 33 + 39 = 72
So;
Average speed = [tex]\frac{total distance}{total time}[/tex] = [tex]\frac{6.8}{72}[/tex] = 0.014
None of the answer choices given is correct.
Fig. 2.1 shows a train
Fig. 2.1
The total mass of the train and its passengers is 750000kg. The train is travelling at a speed of 84m/s.
The driver applies the brakes and the train takes 80s to slow down to a speed of 42m/s.
(a) Calculate the impulse applied to the train as it slows down,
impulse =
[3]
(b) Calculate the average resultant force applied to the train as it slows down,
force =
(2)
Answer:
[tex]\mathrm{(a)\:}32,000,000\:\mathrm{Ns},\\\mathrm{(b)\:}390,000\:\mathrm{N}[/tex]
Explanation:
The impulse-momentum theorem states the impulse on an object is equal to the change in momentum of that object. Momentum is given by [tex]p=mv[/tex]. Since mass is constant, the train's change in momentum is:
[tex]\Delta p=m\Delta v=750,000\cdot42=31,500,000=\fbox{$32,000,000\:\mathrm{Ns}$}[/tex](two significant figures).
Impulse is also given as [tex]\Delta p = F\Delta t[/tex], where [tex]F[/tex] is the average force applied and [tex]\Delta t[/tex] is change in time. Since [tex]t[/tex] is given as [tex]80\mathrm{s}[/tex], we have the following equation:
[tex]F\Delta t=\Delta p\\\\F=\frac{\Delta p}{\Delta t},\\\\F=\frac{31,500,000}{80},\\\\F=393,750=\fbox{$390,000\:\mathrm{N}$}[/tex](two significant figures).
A ball falls from a tower
a) The two forces acting on the tennis ball are equal and opposite. What is the resultant force
?acting on the ball
Answer:
Zero
Explanation:
The resultant force acting on the ball would be zero.
Since only two forces were acting on the tennis ball and these forces negate and cancel each other in magnitude, the resultant effect on the tennis ball would be zero.
Assuming that one of the forces is 5N and acting from the positive side and the other force is also 5N but acting from the negative side.
Resultant = -5 + 5 = 0 N
Nina's measurements, shown in the table here, BEST represent a wave with
A)
decreasing frequency.
B)
increasing frequency.
C)
increasing amplitude.
D)
decreasing amplitude.
Nina's data in this table most accurately depict a wave with decreasing frequency. Option A is right.
What is frequency?A recurring event's frequency is measured by how many times it occurs in a unit of time.
To emphasize distinctions with spatial and angular frequencies, respectively, it is also sometimes referred to as ordinary frequency or temporal frequency.
If the duration, or time interval, required to complete one cycle or vibration is half a second, the frequency is 2 per second; if it is one hundredth of an hour, the frequency is 100 per hour.
The frequency and period, or time interval, are often reciprocally equal, therefore frequency = 1/period = 1 in most circumstances.
The Moon rotates about Earth about a little bit more than 12 times a year. In a violin A string vibrates at a frequency of 440 cycles per second.
Thus, the correct option is A.
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An empty airplane with a mass of 200,000 kg must have a speed of 82 m/s to achieve takeoff. Once it is fully loaded, the airplane has a mass of 350,000 kg. It has 3200 m of runway. a) How much force is needed to get the full airplane safely in the air?
b) How much runway would the empty airplane use if its engines generated the same force?
Answer:
a) A force of 367718.75 newtons is needed to get the full airplane safely in the air.
b) The empty airplane would need a runway of 1828.571 meters.
Explanation:
a) This problem can be solved by using the Work-Energy Theorem, which states that work needed by the airplane to get minimum speed is equal to its change in translational kinetic energy, both measured in joules. The resulting formula is presented below:
[tex]F\cdot \Delta s = \frac{1}{2}\cdot m \cdot (v_{f}^{2}-v_{o}^{2})[/tex] (1)
Where:
[tex]F[/tex] - Minimum net force, measured in newtons.
[tex]\Delta s[/tex] - Runway length, measured in meters.
[tex]m[/tex] - Mass of the airplane, measured in kilograms.
[tex]v_{o}[/tex], [tex]v_{f}[/tex] - Initial and final speeds of the airplane, measured in meters per second.
If we know that [tex]m = 350000\,kg[/tex], [tex]v_{o} = 0\,\frac{m}{s}[/tex], [tex]v_{f} = 82\,\frac{m}{s}[/tex] and [tex]\Delta s = 3200\,m[/tex], then the minimum net force needed by the airplane to get itself safely in the air:
[tex]F = \frac{m\cdot (v_{f}^{2}-v_{o}^{2})}{2\cdot \Delta s}[/tex]
[tex]F = \frac{(350000\,kg)\cdot \left[\left(82\,\frac{m}{s} \right)^{2}-\left(0\,\frac{m}{s} \right)^{2}\right]}{2\cdot (3200\,m)}[/tex]
[tex]F = 367718.75\,N[/tex]
A force of 367718.75 newtons is needed to get the full airplane safely in the air.
b) If we know that [tex]m = 200000\,kg[/tex], [tex]v_{o} = 0\,\frac{m}{s}[/tex], [tex]v_{f} = 82\,\frac{m}{s}[/tex] and [tex]F = 367718.75\,N[/tex], then the length of the runway is:
[tex]\Delta s = \frac{m\cdot (v_{f}^{2}-v_{o}^{2})}{2\cdot F}[/tex]
[tex]\Delta s = \frac{(200000\,kg)\cdot \left[\left(82\,\frac{m}{s} \right)^{2}-\left(0\,\frac{m}{s} \right)^{2}\right]}{2\cdot (367718.75\,N)}[/tex]
[tex]\Delta s = 1828.571\,m[/tex]
The empty airplane would need a runway of 1828.571 meters.
A bucket is filled partly with water such that its combined mass is 2.5 kg. It is tied to a rope and whirled in a circle with a radius of 1.4 m. The speed at the top of the circle is 4.0 m/s and the speed at the bottom of the circle is 6.0 m/s. Determine the magnitude of the net force acting on the bucket at the bottom of the circle.
Answer:
1. Simply τ = m x g x r = 54kg x 9.8m/s² x 0.050m = 26 N·m
2. The bucket creates a torque
τ = 75kg x 9.8m/s² x 0.075m = 55 N·m,
so we must create the same torque with the handle.
55 N·m = F x 0.25m
F = 220 N
Explanation:
Hope this is helpful
Explain how the design of a racing car makes it less likely to turn over.
The principles which allow aircraft to fly are also applicable in car racing. The only difference being the wing or airfoil shape is mounted upside down producing downforce instead of lift. The Bernoulli Effect means that: if a fluid (gas or liquid) flows around an object at different speeds, the slower moving fluid will exert more pressure than the faster moving fluid on the object. The object will then be forced toward the faster moving fluid. The wing of an airplane is shaped so that the air moving over the top of the wing moves faster than the air beneath it. Since the air pressure under the wing is greater than that above the wing, lift is produced. The shape of the Indy car exhibits the same principle. The shape of the chasis is similar to an upside down airfoil. The air moving under the car moves faster than that above it, creating downforce or negative lift on the car. Airfoils or wings are also used in the front and rear of the car in an effort to generate more downforce. Downforce is necessary in maintaining high speeds through the corners and forces the car to the track. Light planes can take off at slower speeds than a ground effects race car can generate on the track. An Indy ground effect race car can reach speeds in excess of 230 mph using downforce. In addition the shape of the underbody (an inverted wing) creates an area of low pressure between the bottom of the car and the racing surface. This sucks the car to road which results in higher cornering speeds.
The total aerodynamic package of the race car is emphasized now more than ever before. Teams that plan on staying competitive use track testing and wind tunnels to develop the most efficient aerodynamic design. The focus of their efforts is on the aerodynamic forces of negative lift or downforce and drag. The relationship between drag and downforce is especially important. Aerodynamic improvements in wings are directed at generating downforce on the race car with a minimum of drag. Downforce is necessary for maintaining speed through the corners. Unwanted drag which accompanies downforce will slow the car. The efficient design of a chassis is based on a downforce/drag compromise. In addition the specific race circuit will place a different demand on the aerodynamic setup of the car.
A road course with low speed corners, requires a car setup with a high downforce package. A high downforce package is necessary to maintain speeds in the corners and to reduce wear on the brakes. This setup includes large front and rear wings. The front wings have additional flaps which are adjustable. The rear wing is made up of three sections that maximize downforce.
The speedway setup looks much different. The front and rear wings are almost flat and are used as stabilizers. The major downforce is found in the shape of the body and underbody. Drag reduction is more critical on the speedway than on other circuits. Since the drag force is proportional to the square of the speed, minimizing drag is a primary concern in the speedway setup. Lap speeds can average over 228 mph and top speeds can exceed 240 mph on a speedway circuit. Effective use of downforce is especially pronounced in highspeed corners. A race car traveling at 200 mph. can generate downforce that is approximately twice its own weight.
Generating the necessary downforce is concentrated in three specific areas of the car. The ongoing challenge for team engineers is to fine tune the airflow around these areas.
What are five facts about magnets? Please help me
Imagine you are dating a mineral sample that contains one-eighth of its original parent isotope. What is the
absolute age of the sample if the half-life of the parent isotope is 15 years?
A. 1.875 years
B. 23 years
C. 45 years
D. 120 years
The age of the sample can be determined using the first order equation of the nuclear decay. The age of the parent isotope here is 45 years.
What is half life ?Unstable radioactive nuclei undergo nuclear decay to produce more stable nuclei with more life time. The time required to decay half of the initial amount of a material is called its half life.
The half life of a sample is related with the decay constant k as follows:
k = 0.693/t1/2
Given that, t1/2 = 15 years
k = 0.693/15 = 0.0462 yr⁻¹
The first order equation of the decay process is written as:
k = 1/t ln w0/wt
where w0 is the initial amount and wt be the amount after time t.
then t = 1/k ln w0/wt
Given that, the sample was decayed to one eighth of the initial amount .
t = 1/k ln 8
= 1/0.0462 ln 8
= 45 years.
Therefore, option C is correct.
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Einstein calculated that ripples of gravity travel at exactly the speed of _____
Answer:
299,792,458 m/s = speed of light
Explanation:
An astronaut sitting on the launch pad on Earth's surface is 6,400 kilometers from Earth's center and weighs 400 newtons. Calculate her weight when she reaches an altitude of 6,400 kilometers above the surface of Earth.
Answer:
weight at height = 100 N .
Explanation:
The problem relates to variation of weight due to change in height .
Let g₀ and g₁ be acceleration due to gravity , m is mass of the object .
At the surface :
Applying Newton's law of gravitation
mg₀ = G Mm / R²
At height h from centre
mg₁ = G Mm /h²
Given mg₀ = 400 N
400 = G Mm / R²
400 = G Mm / (6400 x 10³ )²
G Mm = 400 x (6400 x 10³ )²
At height h from centre
mg₁ = 400 x (6400 x 10³ )²/ ( 2 x 6400 x 10³)²
= 400 / 4
= 100 N .
weight at height = 100 N
it serves as the fuctional unit of the nervous system
Answer:
i would say the neuron
whats the result of rounding 52.8015 into five significant figures
Answer:
52.802
Explanation:
"Significant figures" in Mathematics refer to the digits that give accuracy to the value of a measurement. There are specific rules when it comes to determining the significant figures. For example, all non-zero digits are considered significant and zeroes located in-between non-zero numbers are significant. In the number given above, the digit "0" is located between "8" and "1," therefore, it is significant. All the digits above are significant.
The problem is only asking for "five" significant figures. We can do this by counting from the left to the right. By this means, we know that the number will be rounded off to the nearest thousandths, which is "1." The number after 1 is 5, which means that 1 digit will be added to number 1, thus, making the digit into "2." The last digit (5) will then be removed.
Explanation:
five significant of 52.8015=52.801 ..
how to make measurements of length, volume and time?
Answer:
The volume of a regular object can be calculated by multiplying its length by its width by its height. Since each of those is a linear measurement, we say that units of volume are derived from units of length.
Explanation:
Answer:
length×Width×Height
Explanation:
Length×Width×Height is the formula for volume
A 4.00 kg block is pushed along the ceiling with a constant applied force of 85.0 N that acts at an angle of 55.0 degrees with the horizontal. The block accelerates to the right at 6.00 m/s2. Determine the coefficient of kinetic friction between block and ceiling.
Answer:
0.35
Explanation:
According to Newton's second law;
\sum Fx = ma
Fm - Ff =ma
Fm is the moving force = Wsin theta
Fm = 4(9.8)sin55
Fm = 32.1N
Ff is the frictional force = nmgcos theta
Ff = n(4)(9.8)cos55
Ff = 22.48n
Acceleration a = 6.0m/s²
Substitute the given values into the formula and get the coefficient of friction
32.11-23.48n = 4(6)
32.11-24= 23.48n
8.11 = 23.48
n = 8.11/23.48
n = 0.35
Hence the coefficient of friction is 0.35
When can a high speed velocity cause damage?'
Answer:
50 Mph.
Explanation:
According to the National Severe Storms Laboratory, winds can really begin to cause damage when they reach 50 mph. But here’s what happens before and after they reach that threshold, according to the Beaufort Wind Scale (showing estimated wind speeds): - at 19 to 24 mph, smaller trees begin to sway.
How would I solve this? It's Newton's 2nd law
Answer:
5.65 m/s²
Explanation:
We'll begin by calculating the mass of PJ when in San Diego (i.e Earth). This can be obtained as follow:
Weight of PJ on Earth (Wₑ) = 545 N
Acceleration due to gravity (g) on Earth (gₑ) = 10 m/s²
Mass of PJ on Earth (mₑ) =.?
Wₑ = mₑ × gₑ
545 = mₑ × 10
Divide both side by 10
mₑ = 545 / 10
mₑ = 54.5 Kg
Thus, the mass of PJ on San Diego (i.e Earth) is 54.5 Kg
Finally, we shall determine the acceleration due to gravity of planet Koja. This can be obtained as follow:
Weight of PJ on Koja (Wₖ) = 308 N
Mass of PJ on Koja (mₖ) = mass of PJ on Earth (mₑ) because mass is constant irrespective of location.
Mass of PJ on Earth (mₑ) = 54.5 Kg
Mass of PJ on Koja (mₖ) = 54.5 Kg
Acceleration due to gravity of on Koja (gₖ) =?
Wₖ = mₖ × gₖ
308 = 54.5 × gₖ
Divide both side by 54.5
gₖ = 308 / 54.5
gₖ = 5.65 m/s²
Thus, the acceleration due to gravity on planet Koja is 5.65 m/s²
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]
The middle one please it’s due in 40 min
Answer:
3240000000 Joules
Explanation:
Puck 1 is moving 10 m/s to the left and puck 2 is moving 8 m/s to the right. They have the same mass, m.
a. What is the total momentum of the system before the collision? (Answer in terms of the mass, m.) (0.5 points)
b. What is the total momentum of the system after the collision? (Answer in terms of the mass, m.) (0.5 points)
c. Write puck 1's velocity after the collision in component form. (1 point)
d. What is the y-component of puck 2's velocity after the collision? (1 point)
e. What is the x-component of puck 2's velocity after the collision? (1 point)
f. At what angle does puck 2 move after the collision? Determine the angle and draw it on the diagram. (1 point)
g. What is the magnitude of puck 2's velocity after the collision? (1 point)
Answer:
(a) the total momentum of the system before the collision = -2m kg.m/s.
(b) the total momentum of the system after the collision = -2m kg.m/s.
(c) puck 1's velocity after the collision in component form = (5.44 i, 2.54 j)
Explanation:
Given;
mass of Puck 1 , = m
mass of Puck 2, = m (since they have the same mass m)
initial velocity of Puck 1, u₁ = 10 m/s to the left
initial velocity of Puck 2, u₂ = 8 m/s to the right
Let the rightward direction be positive direction
Let the leftward direction be negative direction
(a) the total momentum of the system before the collision;
P₁ = (initial momentum of Pluck 1) + (initial momentum of Pluck 2)
P₁ = (-mu₁) + mu₂
P₁ = mu₂ - mu₁
P₁ = m(u₂ - u₁)
P₁ = m(8 - 10)
P₁ = -2m kg.m/s
(b) the total momentum of the system after the collision;
Based on the principle of conservation of linear momentum, the total momentum before collision is equal to the total momentum after collision.
Thus, the total momentum of the system after the collision is -2m kg.m/s.
(c) puck 1's velocity after the collision in component form
[tex]v = (v_x, v_y)\\\\v = (vcos \theta , vsin \theta)\\\\v = (6cos 25^0 , 6sin25^0)\\\\v = (5.44i, 2.54j)m/s[/tex]
Appliances connected so that they form a single pathway for
charges to flow are connected in a(n)
A. series circuit.
B. parallel circuit.
C. off circuit.
D. open circuit
Appliances connected so that they form a single pathway for charges to flow are connected in a(n)
Answer:A. Series circuit
#CARRYONLEARNING #STUDYWELLAppliances connected so that they create a single pathway for charges to flow are connected in a series circuit. Therefore, option (A) is correct.
What is the resistance of resistors connected in series?In a series combination of appliances, they are connected end-to-end. Consider two resistors, R₁ and R₂ which are connected in a series combination then their effective resistance can be given by:
Total Resistance of the series circuit, R = R₁ + R₂
In a series combination, the current flows through one appliance and then through another appliance. The same current flows through each appliance in one direction. The total voltage of the series circuit is equal to the sum of all the voltage drops across all appliances.
A potential difference of the series circuit, V = V₁ + V₂
Therefore, when appliances are connected in a series circuit they form a single pathway for charges to flow.
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can someone please help me it’s 15 points of my major grade..
a.
b.
c.
e.
f.
g.
character limit thing
The phases of the moon are caused by which of the following
A. Earths rotation around its axis
B. Earths orbit around the sun
C. The moons orbit around the earth
D. Earths shadow falling on the moon
Answer: C: The moons orbit around the earth.
Explanation:
what volume of alcohol will have the same mass as 4.2m^3 of petrol? (density of alcohol 0.4kg/m^3 and petrol is 0.3kg/m^3)
Answer:
3.15m³
Explanation:
To solve this problem, let us first find the mass of the petrol from the given dimension.
Mass = density x volume
Volume of petrol = 4.2m³
Density of petrol = 0.3kgm⁻³
Mass of petrol = 4.2 x 0.3 = 1.26kg
So;
We can now find the volume of the alcohol
Volume of alcohol = [tex]\frac{mass}{density}[/tex]
Mass of alcohol = 1.26kg
Density of alcohol = 0.4kgm⁻³
Volume of alcohol = [tex]\frac{1.26}{0.4}[/tex] = 3.15m³
Please help ASAP please ASAP
When fireworks explode, sound and light are produced. These are examples of(1 point)
macroscopic inputs.
macroscopic outputs.
microscopic inputs.
microscopic outputs.
Answer: macroscopic outputs
Explanation:
When fireworks explode, sound and light are produced. These are examples of macroscopic outputs. Because, explosion from fireworks is an exothermic process which releases massive heat energy to the surroundings.
What is exothermic reaction?Exothermic reaction are those which evolve heat energy to the surroundings. The change in enthalpy of the reaction is negative here. Whereas, in an endothermic reaction energy is absorbed by the reactants.
Exothermic reactions sometimes results in massive explosion. The heat energy released to the surroundings from the fire works is macroscopic level.
The small scale process or quantity that cannot be measured using normal scales are called microscopic units. Therefore, the sound, light, and heat from the explosion all are macroscopic outputs.
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A vector
of magnitude 5 units and another vector ū of magnitude 3 units point in directions
differing by 60°. Find out (a) the scalar product of the two vectors and (b) the vector product of the two vectors
Answer:
7.5 units
13 units
Explanation:
[tex]|v|=5\ \text{units}[/tex]
[tex]|u|=3\ \text{units}[/tex]
[tex]\theta[/tex] = Angle between the vectors = [tex]60^{\circ}[/tex]
Scalar product is given by
[tex]u\cdot v=|u||v|\cos\theta\\ =3\cdot 5\cdot \cos60^{\circ}\\ =7.5\ \text{units}[/tex]
The scalar product of the vectors is 7.5 units.
Vector product is given by
[tex]u\times v=|u||v|\sin\theta\\ =3\times 5\sin60^{\circ}\\ =13\ \text{units}[/tex]
The vector product of the vectors is 13 units.
An object, 5 cm high, is placed on the principal axis of a diverging lens of focal length 20 cm. The object is 30 cm from the lens.
Use a scaled diagram to locate the image formed by the lens.
Answer:
The answer is 70 cm
Explanation:
If you add All the numbers together, you receive an 55 cm then you add 15 because the points on the diagram also count.