Four compasses are placed on a table top

A spring hangs from the ceiling with an unstretched length of x 0 = 0.69 m x0=0.69 m . A m 1 = 7.5 kg m1=7.5 kg block is hung fr

sergejj [24]

Answer:

x2=0.732m

Explanation:

We can calculate the spring constant using the equilibrium equation of the block m1. Since the spring is in equilibrium, we can say that the acceleration of the block is equal to zero. So, its equilibrium equation is:

$m_1g-k\Delta x_1=0\\\\\implies k=\frac{m_1g}{\Delta x_1}\\\\k=\frac{(7.5kg)(9.8m/s^{2})}{0.84m-0.69m}=490N/m$

Then using the equilibrium equation of the block m2, we have:

$m_2g-k\Delta x_2=0\\\\\\implies x_2=x_0+\frac{m_2g}{k} \\x_2=0.69m+\frac{(2.1kg)(9.8m/s^{2})}{490N/m}= 0.732m$

In words, the lenght x2 of the spring when the m2 block is hung from it, is 0.732m.

6 0

3 years ago

In 1 km races, runner 1 on track 1 (with time 2 min, 28.13 s) appears to be faster than runner 2 on track 2 (2 min, 28.48 s). ho

Murrr4er [49]

We are given with a velocity-distance-time kinematic problem given the different times of two runners and is asked for the difference in distances the runner has ran in the track. we use the formula v= d/t where d is the distance of running, t is time and v is the velocity of the runner.

First runner,
v = d/t = 1000 m / (120+28.13s ) = 6.750826976 m/s
Second runner
Using the same velocity we determine d2.
v = d2/t2 = d2 / (120+28.48s) = 6.750826976 m/s ; d2 = 1002.362789

distance of running track is the difference of the two distance achieved by the runners, delta d= d2 - d = 2.362789 m

3 0

3 years ago

Determine the kinetic energy of a 625-kg roller coaster car that is moving with a speed of 10 m/s.

abruzzese [7]

Hi there!

Kinetic energy can be calculated using the following:

$\large\boxed{KE = \frac{1}{2}mv^2}}$

Where:

KE = Kinetic energy (J)

m = mass (kg)

v = velocity (m/s)

Plug in the given values:

$KE = \frac{1}{2}(625)(10^2) = \boxed{31250J}$

5 0

2 years ago

Read 2 more answers

Given the thermochemical equations X2+3Y2⟶2XY3ΔH1=−370 kJ X2+2Z2⟶2XZ2ΔH2=−120 kJ 2Y2+Z2⟶2Y2ZΔH3=−270 kJ Calculate the change in

Alchen [17]

Answer : The change in enthalpy of the reaction is, -310 kJ

According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.

According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.

The given main reaction is,

$4XY_3+7Z_2\rightarrow 6Y_2Z+4XZ_2$ $\Delta H=?$

The intermediate balanced chemical reaction will be,

(1) $X_2+3Y_2\rightarrow 2XY_3$ $\Delta H_1=-370kJ$

(2) $X_2+2Z_2\rightarrow 2XZ_2$ $\Delta H_2=-120kJ$

(3) $2Y_2+Z_2\rightarrow 2Y_2Z$ $\Delta H_3=-270kJ$

Now we will reverse the reaction 1 and multiply reaction 1 by 2, reaction 2 by 2 and reaction 3 by 3 then adding all the equations, we get :

(1) $4XY_3\rightarrow 2X_2+6Y_2$ $\Delta H_1=2\times (+370kJ)=740kJ$

(2) $2X_2+4Z_2\rightarrow 4XZ_2$ $\Delta H_2=2\times (-120kJ)=-240kJ$

(3) $6Y_2+3Z_2\rightarrow 6Y_2Z$ $\Delta H_3=3\times (-270kJ)=-810kJ$

The expression for enthalpy of formation of $CH_4$ will be,

$\Delta H=\Delta H_1+\Delta H_2+\Delta H_3$

$\Delta H=(+740kJ)+(-240kJ)+(-810kJ)$

$\Delta H=-310kJ$

Therefore, the change in enthalpy of the reaction is, -310 kJ

5 0

3 years ago

A man pulls a 50.0 kg box with a rope parallel to the ground he pulls the box 10.0 m about how much work has he done

anygoal [31]

Your answer is 5000 J

when W(work) = F X when F= the force and X= the displacment

and F(g) = M a(g) when M= mass and a = the acceleration and in our question
, the force is the gravitational force and a= 9.8 m/S2 we can assume as 10 m/s2

and when we have M= 50 Kg
so by substitution:
F= 50 x 10 = 500 N

and by substitution in work equation: when x = 10 m
∴ W = 500 x 10 = 5000 j

4 0

3 years ago

Read 2 more answers