All categories

3 years ago

Should the practice of lining waterways with concrete continue?

Physics

1 answer:

fiasKO [112]3 years ago

5 0

Answer:

Yes, the practice of lining waterways with concrete should continue.

Explanation:

These concrete linings create more laminar flow along the waterways, and in turn, this can reduce erosion. When erosion is reduced, this prevents damage to homes and roads, and loss of land.

You might be interested in

Most meteor showers are associated with the orbits of

MrRissso [65]

Comets.

Small fragments of meteors, formed by ice and rock mixed consitute the comets.

3 0

3 years ago

Read 2 more answers

A 2 kg body is dropped from a height of 3 m. Calculate:

NikAS [45]

Answer:

a) 6.26 m/s

b) 7.67 m/s

Explanation:

The potential energy at height h0 is initially ...

PE0 = mgh0

At height h1, the potential energy is ...

PE1 = mgh1

The difference in potential energy is converted to kinetic energy:

PE0 -PE1 = KE1 = (1/2)m(v1)^2

Solving for v1, we have ...

mg(h0 -h1) = (1/2)m(v1)^2

2g(h0 -h1) = (v1)^2

v1 = √(2g(h0 -h1))

a) When the body is 1 m high, its speed is ...

v = √(2(9.8)(3 -1)) ≈ 6.26 m/s . . . at 1 m high

b) When the body is 0 m high, its speed is ...

v = √(2(9.8)(3 -0)) ≈ 7.67 m/s . . . when it reaches the ground

3 0

3 years ago

A 2200 kg SUV traveling at 23.9 m/s can be stopped in 0.16 s if it hits a concrete wall. Assume that a 60 kg person was in the c

Jlenok [28]

Answer:

8962.5 N

Explanation:

From fundamental kinematics equations, acceleration, a is given by $a=\frac {v-u}{t}$ where v is final velocity, u is initial velocity and t is time

We also know that force is a product of mass and acceleration of an object and substituting $a=\frac {v-u}{t}$ in the formula F=ma we obtain

$F=ma=m\frac {v-u}{t}$ where m is the mass of the body

$F=60\times\frac {0-23.9}{0.16}=-8962.5 N$

Therefore, the force is 8962.5 N

4 0

4 years ago

An object is released from rest at time t = 0 and falls through the air, which exerts a resistive force such that the accelerati

rosijanka [135]

Answer:

A) $\frac{g}{b}(1-e^{-bt})$

Explanation:

Since a = g - bv,

We can substitute a = dv/dt into the equation.

Then, the equation will be like dv/dt = g - bv.

So we got first order differential equation.

As known, v = 0 at t = 0, and v = g/b at t = ∞.

Since $\frac{dv}{dt}= g - bv = b( \frac{g}{b} - v)$ ⇒ $\frac{dv}{ \frac{g}{b} - v}= bdt$

So take the integral of both side.

$- ln (\frac{g}{b} - v) = bt + C$

Since for t=0, v = 0 ⇒ $C =- ln (\frac{g}{b})$

$v = \frac{g}{b} + e^{-bt-ln(\frac{g}{b})} = \frac{g}{b}- \frac{g}{b}e^{-bt} = \frac{g}{b}(1-e^{-bt})$

5 0

3 years ago

When a police officer catches you speeding by using a radar gun, the waves sent out by the gun must be _______ off your car.

Neporo4naja [7]

I would say its Absorbed

7 0

3 years ago