Increasing cardiorespiratory fitness levels is difficult for experienced athletes because _________

Jon and Jim push a dead car forward to the gas station. Jon pushes with 90N while Jim pushes 80 N.

Nina [5.8K]

The resultant of the two forces is about 170 N.

<h3>What is the resultant force?</h3>

The term resultant force has to do with the single force that has the same magnitude and direction as two or more forces acting together.

In this case, the both forces are acting in the forward direction. This implies that the resultant force is 90 N + 80 N = 170 N.

Learn more about resultant force:brainly.com/question/16380983

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5 0

2 years ago

3.

Alexxx [7]

Answer:

120°

Explanation:

Draw a free body diagram. There are three forces acting on the traffic light. Two tension forces acting along the cables, and weight.

The tension forces have an angle θ between them. That means each tension force forms an angle of θ/2 with respect to the vertical. So the y component of each tension force is:

Ty = T cos (θ/2)

Sum of the forces in the y direction:

∑F = ma

Ty + Ty − W = 0

2 Ty = W

Substituting:

2 T cos (θ/2) = W

If W = T, then:

2 W cos (θ/2) = W

2 cos (θ/2) = 1

cos (θ/2) = 1/2

θ/2 = 60°

θ = 120°

6 0

4 years ago

An ohmic dipole of resistance 100 ohm is crossed by a current of intensity 120 ma. Calculates the voltage across this chemical d

Sedaia [141]

Answer:

12.0 Volt

Explanation:

Step 1: Given data

Resistance of the ohmic dipole (R): 100 Ohm

Intensity of current (I): 120 mA (0.120 A)

Step 2: Calculate the voltage (V) across this chemical dipole

To calculate the voltage across the ohmic dipole, we will use Ohm's law.

I = V/R

V = I × R

V = 0.120 A × 100 Ohm = 12.0 V

4 0

3 years ago

A level test track has a coefficient of road adhesion of 0.80, and a car being tested has a coefficient of rolling friction that

pav-90 [236]

Answer:

the unloaded braking efficiency is 84.6 %

Explanation:

Given the data in the question;

by Ignoring aerodynamic resistance; we can find the theoretical stopping distance using the following formula

S = (Y $_{b}$ ( V₁² - V₂²)) / ( 2g( ηbμ + $f_{rl}$ ± sin∅ $_{g}$ ))

now given that the tracked is levelled, ∅ $_{g}$ = 0, also Y $_{b}$ = 1.04 for level or flat road

Speed V₁ = 60mil/hr = (60×5280)/(1×60×60) = 316800ft/3600s = 88ft/s

now, we substitute in our values to get the braking efficiency;

180ft = (1.04( (88ft/s)² - 0²)) / ( 2(32.2( (ηb/100)(0.80) + (0.018) ± sin(0°)))

180ft = 8053.76 / ( 64.4)(0.008ηb + 0.018)

180ft = 8053.76 / ( 0.5152ηb + 1.1592)

180( 0.5152ηb + 1.1592) = 8053.76

( 0.5152ηb + 1.1592) = 8053.76 /180

0.5152ηb + 1.1592 = 44.7431

0.5152ηb = 44.7431 - 1.1592

0.5152ηb = 43.5839

ηb = 43.5839 / 0.5152

ηb = 84.596 ≈ 84.6 %

Therefore, the unloaded braking efficiency is 84.6 %

7 0

3 years ago

Consider a hydrogen atom in the n = 1 state. The atom is placed in a uniform B field of magnitude 2.5 T. Calculate the energy di

dlinn [17]

Answer:

$E=29\times 10^{-5}eV$

Explanation:

For n-=1 state hydrogen energy level is split into three componets in the presence of external magnetic field. The energies are,

$E^{+}=E+\mu B$ ,

$E^{-}=E-\mu B$ ,

$E^{0}=E$

Here, E is the energy in the absence of electric field.

And

$E^{+} and E^{-}$ are the highest and the lowest energies.

The difference of these energies

$\Delta E=2\mu B$

$\mu=9.3\times 10^{-24}J/T$ is known as Bohr's magneton.

B=2.5 T,

Therefore,

$\Delta E=2(9.3\times 10^{-24}J/T)\times 2.5 T\\\Delta E=46.5\times 10^{-24}J$

Now,

$Delta E=46.5\times 10^{-24}J(\frac{1eV}{1.6\times 10^{-9}J } )\\Delta E=29.05\times 10^{-5}eV\\Delta E\simeq29\times 10^{-5}eV$

Therefore, the energy difference between highest and lowest energy levels in presence of magnetic field is $E=29\times 10^{-5}eV$

6 0

4 years ago

Increasing cardiorespiratory fitness levels is difficult for experienced athletes because __________.