All categories

2 years ago

PLEASE HELP!! ITS URGENT!!!

Physics

1 answer:

Natasha2012 [34]2 years ago

6 0

Answer:

F = 800 [N]

Explanation:

To be able to calculate this problem we must use the principle of momentum before and after the impact of the hammer.

We must summarize that after the impact the hammer does not move, therefore its speed is zero. In this way, we can propose the following equation.

ΣPbefore = ΣPafter

$(m_{1}*v_{1}) - F*t = (m_{1}*v_{2})$

where:

m₁ = mass of the hammer = 0.15 [m/s]

v₁ = velocity of the hammer = 8 [m/s]

F = force [N] (units of Newtons)

t = time = 0.0015 [s]

v₂ = velocity of the hammer after the impact = 0

$(0.15*8)-(F*0.0015) = (0.15*0)\\F*0.0015 = 0.15*8\\F = 1.2/(0.0015)\\F = 800 [N]$

Note: The force is taken as negative since it is exerted by the nail on the hammer and this force is directed in the opposite direction to the movement of the hammer.

You might be interested in

How would you write the number 6,500,000,000 in scientific notation?

photoshop1234 [79]

Scientific form = 6.5 x 109.

8 0

3 years ago

Scientists studying an anomalous magnetic field find that it is inducing a circular electric field in a plane perpendicular to t

yarga [219]

Answer

The rate at which the magnetic field is changing is $[\frac{dB}{dt} ] = 0.000467 T/s$

Explanation

From the question we are told that

The electric field strength is $E = 3.5mV/m = 3.5 *10^{-3} \ V/m$

The radius is $r = 1.5 \ m$

The rate of change of the magnetic field is mathematically represented as

$\frac{d \phi }{dt} = \int\limits^{} {E \cdot dl}$

Where $dl$ is change of a unit length

$\frac{d \phi}{dt} = A * \frac{dB}{dt}$

Where A is the area which is mathematically represented as

$A = \pi r^2$

$E \int\limits^{} { dl} = ( \pi r^2) (\frac{dB}{dt} )$

$E L = ( \pi r^2) (\frac{dB}{dt} )$

where L is the circumference of the circle which is mathematically represented as

$L = 2 \pi r$

$E (2 \pi r ) = (\pi r^2 ) [\frac{dB}{dt} ]$

$E = \frac{r}{2} [\frac{dB}{dt} ]$

$[\frac{dB}{dt} ] = \frac{E}{ \frac{r}{2} }$

substituting values

$[\frac{dB}{dt} ] = \frac{3.5 *10^{-3}}{ \frac{15}{2} }$

$[\frac{dB}{dt} ] = 0.000467 T/s$

8 0

3 years ago

An underwater scuba diver sees the Sun at an apparent angle of 43.0° above the horizontal. What is the actual elevation angle of

Inessa05 [86]

Answer:

The actual elevation angle is 12.87 degrees

Explanation:

In the attachment you can clearly see the situation. The angle of elevation as seen for the scuba diver is shown in magenta, we conclude that $\theta_2=90-43=47$ .

Using Snell's Law we can write:

$n_1\sin(\theta_1)=n_2\sin(\theta_2)$

$\implies \sin(\theta_1)=\frac{n_2}{n_1}\sin(\theta_2)$ ,

Let's approximate the index of refraction of the air (medium 1 in the picture) to 1.

We thus have:

$\sin(\theta_1)=n_2\sin(\theta_2)=1.333\sin(47)$

$\implies\theta_1=\arcsin[n_2\sin(\theta_2)]=\arcsin[1.333\sin(47)]\approx 77.13$ . Calling $\alpha$ the actual angle of elevation, we get from the picture that $\alpha=90-77.13=12.97$

7 0

2 years ago

A rock is thrown upward with an initial velocity of 16 ft/s from an initial height of 5 ft. write a quadratic function equation

Andrei [34K]

During upward projection the final velocity is zero, and the gravitational acceleration is -10 m/s² (against the gravity).
Therefore; using the equation;
S = 1/2gt² + ut
Where s is the height h, g is gravitational acceleration, and t is the time and u is the initial velocity u, is 16 ft/s.
Thus; h= 1/2(-10)t² + 16t
We get; h = -5t² + 16t
Therefore; the quadratic equation is 5t² - 16t + h =0

5 0

3 years ago

25 POINTS FOR ANSWER How are Newton’s Laws used to describe the motion of planets? Justify your response in two or more complete

Alexus [3.1K]

Pour la seule et simple raison qu'elle s'exerce entre tous les corps de l'univers ( objet, astres etc..

Si on tient compte des frottements liés aux chocs successifs des billes les une sur les autre, au bout d'un certain temps, le mouvement va cesser.

Si on dit que toute l'énergie potentielle de pesanteur est transformée en énergie cinétique, et réciproquement, donc que l'énergie mécanique est conservée au fil des chocs et des rebonds, alors, le mouvement est perpétuel. Le nombre de billes qui remontent est toujours égal au nombre de billes qu'on a lâchées.

La première loi concerne des systèmes immobiles, ou plutôt on considère des systèmes dit "isolé", c'est à dire qu'ils ne sont pas soumis à d'autre force que celle que l'on connait.

Ce qu'il faut retenir de celui ci c'est ça :

Si j'ai un système en mouvement rectiligne uniforme OU immobile, alors :

Avec F1 F2 F3, trois forces s'exercant sur mon système

Attention ! Ici je n'ai pas mit les flèches sur les différentes forces mais elles sont obligatoires ! On parle de vecteur force !

Pour la deuxième loi :

C'est le même principe, la différence c'est que l'on est en mouvement.

Avec a le vecteur accélération. Il y a beaucoup de ressource sur le net, n'hésite pas à regarder, la j'ai simplement pu te donner les expressions les plus connus. Mais il faudra les manipuler, et sans exercice sur lequel se baser, c'est plus difficile !

La troisième loi est bien moins importante que les deux autres, mais n'hésite pas à regarder sur le net, tu trouveras l'énoncé. C'est la même logique.

4 0

3 years ago

PLEASE HELP!! ITS URGENT!!!​

PLEASE HELP!! ITS URGENT!!!