How can I find the center of gravity of a human being?

A police officer measures a straight skid mark on the road of length d=20m. the car involved is stationary at the end of the ski

zvonat [6]

80 divided by 20 is 2

8 0

3 years ago

An automobile steering wheel is shown. What is the ideal mechanical advantage? If the AMA is 8, what is the efficiency of the st

Mars2501 [29]

1. Ideal Mechanical Advantage (IMA): 9

Explanation:

For a wheel and axle system like the steering wheel, the IMA is given by:

$IMA=\frac{r_w}{r_a}$

where

$r_w$ is the radius of the wheel

$r_a$ is the radius of the axle

For the steering wheel of the problem, we see that $r_w = 18 cm$ and $r_a=2 cm$ , so the IMA is

$IMA=\frac{18 cm}{2 cm}=9$

2. Efficiency: 88.9%

Explanation:

The efficiency of a system is defined as the ratio between the AMA (actual mechanical advantage) and the IMA:

$\eta=\frac{AMA}{IMA}\cdot 100$

In this problem, AMA=8 and IMA=9, so the efficiency is

$\eta=\frac{8}{9}\cdot 100=88.9\%$

6 0

4 years ago

A kangaroo jumps up with an initial velocity of 36 feet persecond from the ground (assume its starting height is 0 feet).Use the

kkurt [141]

Given

Initial velocity:

36 ft/s

Initial height:

0 ft

Vertical motion model:

h(t) = -16t^2 + ut + s

v = initial velocity

s = is the height

Procedure

We are going to use the model provided for the vertical motion.

$\begin{gathered} h(t)=-16t^2+36t+0 \\ h(t)=-16t^2+36t \end{gathered}$

We know that at the maximum height the final velocity is 0.

Then we will use the following expression to calculate the maximum height:

$\begin{gathered} v^2_f=v^2_o-2ah_{\max } \\ 0=v^2_o-2ah_{\max } \\ 2ah_{\max }=v^2_o \\ h_{\max }=\frac{v^2_o}{2a} \\ h_{\max }=\frac{(36ft/s)^2}{2\cdot32ft/s^2} \\ h_{\max }=20.25\text{ ft} \end{gathered}$

Now for time:

$\begin{gathered} 20.25=-16t^2+36t \\ 16t^2-36t+20.25=0 \end{gathered}$

Solving for t,

$\begin{gathered} t_1=2.25 \\ t_2=0 \end{gathered}$

The total time the kangaroo takes in the air is 2.3s.

3 0

1 year ago

When all parts of a circuit are composed of conducting materials, the circuit is said to be

den301095 [7]

When all parts of a circuit ... all the way from one terminal of the
battery or power supply to the other terminal ... are composed of
conducting materials, then current can flow in the circuit, and the
circuit is said to be 'closed'.

4 0

4 years ago

IN WHAT CONDITION DO SOUND ECHO

DerKrebs [107]

Answer:

The conditions necessary for hearing the echo. The distance between the sound source and the reflecting surface must not be less than 17 metres where the time period between hearing the original sound and its echo should not be less than 0.1 of a second.

6 0

3 years ago