Which of the following is NOT a unit of measurement in the metric system?

An elevator cab and its load have a combined mass of 1200 kg. Find the tension in the supporting cable when the cab, originally

Nadya [2.5K]

Answer:

10044 N

Explanation:

The acceleration of the cab is calculated using the equation of motion:

$v^2 = u^2+2as$

v is the final velocity = 0 m/s in this question, since it is brought to rest

u is the initial velocity = 10 m/s

a is the acceleration

s is the distance = 35 m

$a = \dfrac{v^2-u^2}{2s} = \dfrac{(0 \text{ m/s})^2-(10 \text{ m/s})^2}{2\times (35\text{ m})} = -1.43\text{ m/s}^2$

Since it accelerates downwards, its resultant acceleration is

$a_R = g + a$

g is the acceleration of gravity.

$a_R = (9.8-1.43)\text{ m/s}^2 = 8.37\text{ m/s}^2$

The tension in the cable is

$T = ma_R = (1200\text{ kg})(8.37\text{ m/s}^2) = 10044 \text{ N}$

3 0

3 years ago

The lamborghini murcielago can accelerate from 0 to 27.8 m/s (100 km/hr or 62.2 mi/hr) in a time of 3.40 seconds. Determine the

Ostrovityanka [42]

To determine the acceleration of the car, we use equation of motion

$v = u +at$

Here, v is final velocity of the car, u is the initial velocity of the car, a is the acceleration of the car in time t.

Given, $v = 27.8 \ m/s$ , u=0 because car accelerate from 0 and t = 3.40 s.

Substituting these values in above equation, we get

$27.8 \ m/s = 0 + a \times 3.40 \ s \\\\ a= \frac{27 .8 m/s}{3.40\ s} = 8.17 \ m/s^2$

In mi/ h.s,

1 m = 0.000621371 mile.

1 s = (1/3600 ) hour = 0.000277778 hour.

Therefore,

$8.17 \ m/s^2 = 18.2757695061 \ mi/h.s (mile \ per \ hour \ second)$

6 0

3 years ago

Read 2 more answers

A mass weighing 4 pounds is attached to a spring whose constant is 2 lb/ft. The medium offers a damping force that is numericall

Ad libitum [116K]

Answer:

t = 025 s

Explanation:

We know

weight, W = 4 pounds

spring constant, k = 2 lb/ft

Positive damping, β = 1

Therefore mass, m = W / g

m = 4 / 32

= 1 / 8 slug

From Newtons 2nd law

$\frac{d^{2}x}{dt^{2}}=-kx-\beta .\frac{dx}{dt}$

where x(t) is the displacement from the mean or equilibrium position. The equation can be written as

$\frac{d^{2}x}{dt^{2}}+\frac{\beta }{m}.\frac{dx}{dt}+\frac{k}{m}x=0$

Substituting the values, the DE becomes

$\frac{d^{2}x}{dt^{2}}+8\frac{dx}{dt}+16x=0$

Now the equation is

$m^{2}+8m+16=0$

and on solving the roots are

$m_{1}$ = $m_{2}$ = -4

Therefore the general solution is $x(t)=e^{-4t}\left ( c_{1}+c_{2}t \right )$

Now for initial condition x(0) = -1 ft

x'(0)= 8 ft/s

Now we can find the equation of motion becomes,

$x(t)=e^{-4t}\left ( -1+4t \right )$

Therefore, the mass passes through the equilibrium when

x(t) = 0

$e^{-4t}\left ( -1+4t \right )$ = 0

-1+4t = 0

t = $\frac{1}{4}$

= 0.25 s

8 0

3 years ago

Which statement best describes the movement of atoms in a solid?

Helga [31]

Answer:

They have no freedom to move

Explanation:

Particles can be solids, liquids and gases.

Solids are the substances in which the atoms are very close to each other. It is very difficult to separate the molecules. The atoms cannot move from one place to another. The inter molecular forces between them is very strong.

Hence, the correct option that describes the movement of atoms in a solid is (c) "They have no freedom to move".

5 0

3 years ago

An ideal gas initially at 275 k undergoes an isobaric expansion at 2.50 kpa. the volume increases from 1.00 m3 to 3.00 m3 and 11

tekilochka [14]

The transformation is isobaric (constant pressure), so the work done by the gas is the product between its pressure and the variation of volume:
$W=p \Delta V=(2500 Pa)(3.0 m^3-1.0 m^2 ) = +5000 J =+5.0 kJ$

The heat transferred to the gas is
$Q=+11.2 kJ$

So we can use the first law of thermodynamics to compute the variation of internal energy of the gas:
$\Delta U = Q-W=11.2 kJ-5.0 kJ=+6.2 kJ = +6200 J$
where the positive sign means the internal energy of the gas has increased.

5 0

4 years ago