All categories

4 years ago

A rubber band has a spring constant of 15 N/m. If you stretch it by 0.3 m,

Physics

1 answer:

borishaifa [10]4 years ago

5 0

Answer:

B. 4.5N

Explanation:

F = kx

Where

F = force

K = spring constant

x = compression

Given

K = 15N/m

x = 0.3m

Therefore

F = 15 x 0.3

F = 4.5N

The magnitude of the force that resists the stretching is 4.5N

You might be interested in

PLZ HURRY WILL GIVE BRAINILEST!!:D

Colt1911 [192]

Answer:

b why is Alice suddenly so thirsty i think

3 0

3 years ago

Read 2 more answers

A 480 g peregrine falcon reaches a speed of 69 m/s in a vertical dive called a stoop. If we assume that the falcon speeds up und

LiRa [457]

Answer:

The minimun height is 242 [m]

Explanation:

We can solve this problem by using the principle of energy conservation, where potential energy becomes kinetic energy. We will take the point where the Falcon reaches the speed of 69 (m/s), as the point where the potential energy is zero, i.e. it will be the reference point.

At the reference point all potential energy has been transformed into kinetic energy, therefore the kinetic energy can be calculated.

$E_{k}=0.5*m*v^{2} \\ where:\\v = velocity = 69 [m/s]\\m = mass = 480[g] = 0.480[kg]\\E_{k} = kinetic energy [J]\\E_{k} =0.5*0.48*(69)^{2} \\E_{k} =1142.64[J]$

Now we can calculate the elevation with respect to the reference point using the definition of the potential energy.

$E_{p}=m*g*h\\ E_{p}=E_{k} \\therefore\\h= E_{p}/(m*g)\\h= 1142.64/(.48*9.81)\\h=242[m]$

4 0

3 years ago

What properties are different between blue light and red light?

Oksi-84 [34.3K]

Blue light has a shorter wavelength than does red light, and since it travels at the same speed (in vacuum) as red light, has a higher frequency. This gives it a higher energy per photon.

3 0

3 years ago

A water discharge of 9 m3/s is to flow through this horizontal pipe, which is 0.98 m in diameter. If the head loss is given as 1

Mashutka [201]

Answer: The power required by the pump to produce a discharge of 9m³/s is 5990joules/secs.

Explanation: The given parameters from the questions are:

Flow rate Q = 9m³/s, Diameter D = 0.98m, acceleration a = 1.0, head loss(Pressure P) is given by the function 10v²/2g.

STEP 1. Find the velocity of water in the pipe from the equation:

Diameter D = (√4.Q/π.v), where v is the velocity, and Q is flow rate

Making v subject of the formula gives:

v = 4Q/π.√D =[ 4 × 9m³/s / 3.142 × (√0.98m)] = 11.69m/s.

STEP 2. Find the pressure from the relationship, P = 10v²/2g, NB. g = a

P = 10 × (11.69m/s)² / 2× 1.0m/s²

P = 683.25N/m² or Pascal.

STEP 3. Find force exerted by the pump;

Recall that Pressure P = Force/Area

But Area A = π.r², where r = D/2

Therefore, A = π.(D/2)²

A = 3.142 × [0.98m/2]² = 0.75m²

Therefore, Force = Pressure × Area

Force F = 683.25N/m² × 0.75m²

F = 512.44N.

STEP 4. Find work done

Work done W by the pump is = Force × distance d moved by the water

W = F . d

Also recall that flow rate Q = Velocity/time.

Q = v/t, we can write t = v/Q.

Time t = 11.69m/s / 9m³/s = 1.298s

Also recall that velocity v = distance d/time t, v = d/t, making d subject of formula gives v × t

Distance d = v × t = 11.69m/s × 1.298s = 15.17m.

Hence,

Work Done W = Force × distance

W = 512.44N × 15.17m = 7775.56Nm or joules.

Lastly, Power P = Work done/ time

P = 7775.56joules/1.298s

P = 5990.4joules/s.

8 0

3 years ago

A 1000 kg red car traveling at 40 m/s rear ends a 3000 kg blue car traveling at 35 m/s. the cars bounce off each other and the b

klemol [59]

Answer:

32.5 ms⁻¹

Explanation:

Theory

The law of conservation of linear momentum

The sum of linear momentum of a system under no external force remains constant.

In this scenario although different forces act on two vehicles by each other when we consider the total system of two cars no external unbalance force act on them. So we can apply this law.

As law says,

The sum of linear momentum before collision = The sum of linear momentum after collision.

Momentum = mass × velocity

1000×40+3000×35 = 1000×v + 3000×37.5

where v = velocity of the red car after the cash

v = 32.5 ms⁻¹

8 0

3 years ago