Name the following compound: CH2 = CH2 Ethyne Ethane Ethyl ethane

A person pushes a 10 kg box from rest and accelerates it to a speed of 4 m/s with a constant force. If the box is pushed for a t

lutik1710 [3]

The box is accelerated from rest to 4 m/s in a matter of 2.5 s, so its acceleration a is such that

4 m/s = a (2.5 s) → a = (4 m/s) / (2.5 s) = 1.6 m/s²

Then the force applied to the box has a magnitude F such that

F = (10 kg) (1.6 m/s²) = 16 N

7 0

3 years ago

A 45.0-kg girl is standing on a 168-kg plank. The plank, originally at rest, is free to slide on a frozen lake, which is a flat,

muminat

Answer:

The speed of the plank relative to the ice is:

$v_{p}=-0.33\: m/s$

Explanation:

Here we can use momentum conservation. Do not forget it is relative to the ice.

$m_{g}v_{g}+m_{p}v_{p}=0$ (1)

Where:

m(g) is the mass of the girl
m(p) is the mass of the plank
v(g) is the speed of the girl
v(p) is the speed of the plank

Now, as we have relative velocities, we have:

$v_{g/b}=v_{g}-v_{p}=1.55 \: m/s$ (2)

v(g/b) is the speed of the girl relative to the plank

Solving the system of equations (1) and (2)

$45v_{g}+168v_{p}=0$

$v_{g}-v_{p}=1.55$

$v_{p}=-0.33\: m/s$

I hope it helps you!

8 0

3 years ago

A volcano erupts and launches a chunk of hot magma horizontally with a speed of 252 m/s. The magma travels a horizontal distance

ArbitrLikvidat [17]

Answer:

The value is $v_y = -48.61 \ m/s$

Explanation:

From the question we are told that

The horizontal speed is $u_x = 252 \ m/s$

The horizontal distance is $d = 1250 \ m$

Generally the time taken by the hot magma in air before landing is mathematically represented as

$t = \frac{d}{u_x}$

=> $t = \frac{ 1250 }{252}$

=> $t = 4.96 \ s$

Generally the initial vertical velocity of the magma when it was lunched is

$u_y = 0 \ m/ s$

Then the final velocity of the magma when it hits the ground is mathematically represented s

$- v_y = u_y + gt$

Here the negative sign mean that the direction of the velocity is towards the negative y -axis

So

$- v_y = 48.61 \ m/s$

=> $v_y = -48.61 \ m/s$

7 0

3 years ago

Infer why the output force exerted by a rake must be less than input force?

adell [148]

<h3>Answer and Explanation;</h3>

input force refers to the force exerted on a machine, also known as the effort, while the output force is the force machines produce or the Load. The ratio of output force to input force gives the mechanical advantage of a simple machine
The output force exerted by the rake must be less than the input force because one has to use force while raking. The force used to move the rake is the input force. 
The rake is not going to be able to convert all of the input force into output force, the force the rake applies to move the leaves, because of friction.

5 0

4 years ago

The wave property which is independent of all other properties is

Anna71 [15]

The wave property which is independent of all other properties is THE VELOCITY OF A WAVE.
The velocity of a wave is defined as the distance moved by a cyclic motion per unit time. The velocity of a wave is determined by the properties of the medium through which it moves; it does not not depend on the properties of the wave itself.

3 0

3 years ago