I can use everything on my body to advance the ball but what?

The velocity of a 1.3 kg block sliding down a frictionless inclined plane is found to be 1.26 m/s. 1.10 s later, it has a veloci

nasty-shy [4]

Answer:

$\theta = 25.3^\circ$

Explanation:

The acceleration of the block can be found by the kinematics equations:

$v = v_0 + at\\5.88 = 1.26 + a(1.1)\\a = 4.2~m/s^2$

Since the plane is frictionless, the only force acting on the block along the motion of the block is its weight.

$F = mg\sin(\theta) = ma\\g\sin(\theta) = a\\(9.8)\sin(\theta) = 4.2\\\theta = 25.3^\circ$

7 0

3 years ago

A river 800m wide flows at the rate of 5km/h . A swimmer who can swim at 10km/h in still water wants to cross the river straight

LuckyWell [14K]

Answer:

At an angle of $30^{\circ}$

Explanation:

Assume the river flows from East to West so for the swimmer to cross across it, assume he crosses it from West to East.

The resultant speed will be given by

$R= \sqrt {10^{2}-5^{2}=\sqrt {75}\approx 8.66 km/h\\Direction=sin^{-1}\frac {5}{10}\approx 30^{\circ}$

6 0

3 years ago

A stationary siren emits sound of frequency 1000 Hz and wavelength 0.343 m. An observer who is moving toward the siren will meas

Ainat [17]

Answer:

f>1000Hz and wavelength=0.343 m

Explanation:

We are given that

Frequency of stationary siren,f=1000 Hz

Wavelength of stationary sound, $\lambda=0.343 m$

When a observer is moving towards the siren then the frequency increases.

Therefore,an observer who is moving towards the siren measure a frequency >1000 Hz.

The wavelength depends upon the speed of source.

But we are given that siren is stationary.

Therefore, source is not moving and then the wavelength remains same.

f>1000Hz and wavelength=0.343 m

4 0

3 years ago

Match the phrase with the term. How hard the blood pushes on the inside of the blood vessels is called . The total amount of blo

taurus [48]

Answer:

How hard the blood pushes on the inside of the blood vessels is called? BLOOD PRESSURE

The total amount of blood the heart pumps in one minute is called ?

CARDIAC OUTPUT

When blood vessels open wider during exercise, they are said to ?

DILATE

How many times your heart beats in one minute is called ?

HEART RATE

The force that can put unhealthy tension on the heart as it is pumping is called ?

BLOOD PRESSURE

The amount of blood the heart pumps out in one beat is called?

STROKE VOLUME

Explanation:

4 0

3 years ago

A system consists of electrons and protons only. It contains 150 electrons and has a total charge of +22e. What is the mass of t

liubo4ka [24]

According to the statements the number of electrons is 150, then

e = 150

But there is a positive charge of +22e, then the number of protons would be

p = 150+172

If the mass of the electrons is

$m_e = 9.11*10^{-31} kg$

And the mass of the protong is

$m_p = 1.673*10^{-27}kg$

We have that the total mass of the system would be

$m = e*m_e +pm_p$

$m = 150 * (9.11*10^{-31})+170(1.673*10^{-27})$

$m = 2.84547*10^{-25} kg$

5 0

3 years ago