Ask question

Ask question

All categories

2 years ago

5

An object travels 50 m in 4 s. It had no initial velocity and experiences constant acceleration. What is the magnitude of the ac

celeration?

1 answer:

Allisa [31]2 years ago

3 0

Answer:

The formula to calculate velocity in this case:

v = v0 + at

=> a = (v - v0)/t

= (50 - 0)/4

= 50/4 = 12.5 (m/s2)

Hope this helps!

:)

You might be interested in

In a 1.25-T magnetic field directed vertically upward, a particle having a charge of magnitude 8.50μC and initially moving north

Goshia [24]

Answer:

a) The sign of the charge is positive.

b) The magnetic force on the particle is 0.050 newtons.

Explanation:

The magnetic force F on a moving charge with velocity v passing through a magnetic field B is:

$\overrightarrow{F}=q\overrightarrow{v}\times\overrightarrow{B}$ (1)

a)

Because it is a cross product, we can find the direction of the force using the right-hand rule, that is too the direction of the movement. We have two possibilities here because the velocity vector and magnetic field are perpendicular: the particle deflects towards east or toward west, which depends on the charge of the particle. Note that if you put your right hand fingers, except thumb, pointing towards north (direction of velocity) and later close them in the direction of the magnetic field, if you maintain your thumb perpendicular to this movement it will point towards east (See figure), so that will be de direction of the force if the charge is positive, but if the charge is negative, the direction will be opposite (towards west). So the charge has to be positive to deflects towards east.

b)

Now by 1:

$F=qvB\sin\theta=(8.50\times10^{-6})(4750)(1.25)\sin90\simeq\mathbf{0.050\,N}$

5 0

2 years ago

A 50-g cube of ice, initially at 0.0°C, is dropped into 200 g of water in an 80-g aluminum container, both initially at 30°C.

MakcuM [25]

Answer:

b. 9.5°C

Explanation:

$m_i$ = Mass of ice = 50 g

$T_i$ = Initial temperature of water and Aluminum = 30°C

$L_f$ = Latent heat of fusion = $3.33\times 10^5\ J/kg^{\circ}C$

$m_w$ = Mass of water = 200 g

$c_w$ = Specific heat of water = 4186 J/kg⋅°C

$m_{Al}$ = Mass of Aluminum = 80 g

$c_{Al}$ = Specific heat of Aluminum = 900 J/kg⋅°C

The equation of the system's heat exchange is given by

$m_i(L_f+c_wT)+m_wc_w(T-T_i)+m_{Al}c_{Al}=0\\\Rightarrow 0.05\times (3.33\times 10^5+4186\times T)+0.2\times 4186(T-30)+0.08\times 900(T-30)=0\\\Rightarrow 1118.5T-10626=0\\\Rightarrow T=\dfrac{10626}{1118.5}\\\Rightarrow T=9.50022\ ^{\circ}C$

The final equilibrium temperature is 9.50022°C

4 0

2 years ago

A confused dragonfly flies forward and backward in a straight line. Its motion is shown on the following graph of horizontal pos

sertanlavr [38]

Answer:

0

Explanation:

Assuming your graph and question match the attachment, the average speed is 0. The bug ends up where it started, so its displacement is zero.

average speed = displacement/time = 0/(8 s)

average speed = 0

7 0

2 years ago

Which of these discoveries contradict components of Dalton’s atomic theory? Check all of the boxes that apply. Atoms contain sma

EastWind [94]

Explanation:

According to Dalton's atomic theory, all the atoms are individual, all the atoms of the same element are identical in properties and mass, the compound is formed from two or more kinds of the atoms, all the matter is made up of small atoms and the chemical reaction is a rearrangement of the atoms.

The discoveries which contradicts the components of Dalton's atomic theory from the given discoveries are:

Nuclear reactions can change an atom of one element into an atom of another element.

Atoms of a given element can have different numbers of neutrons.

Atoms contain smaller particles: protons, neutrons, and electrons.

4 0

2 years ago

Read 2 more answers

Two hockey players skating on essentially frictionless ice collide head-on. Madeleine, of mass 65.0 kg, is moving at 6.00 m/s to

xeze [42]

Explanation:

It is given that,

Mass of Madeleine, $m_1=65\ kg$

Initial speed of Madeleine, $u_1=6\ m/s$ (due east)

Final speed of Madeleine, $v_1=-3\ m/s$ (due west)

Mass of Buffy, $m_2=55\ kg$

Final speed of Buffy, $v_2=3.5\ m/s$ (due east)

Let $u_1$ is the Buffy's velocity just before the collision. Using the conservation of linear momentum as :

$m_1u_1+m_2u_2=m_1v_1+m_2v_2$

$65\times 6+55\times u_2=65\times (-3)+55\times 3.5$

$u_2=-7.13\ m/s$

So, the initial speed of the Buffy just before the collision is 7.13 m/s and it is moving due west. Hence, this is the required solution.

5 0

2 years ago