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3 years ago

Which of the following describes plastic? HELP

Physics

1 answer:

Bingel [31]3 years ago

4 0

Answer:

Explanation:

A material that has a high resistivity and prevents charges from moving freely... it is part of insulators...

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according to newton's second law of motion of the net force acting on the object increases while the mass of the object remains

Licemer1 [7]

Answer:

The Acceleration will increase

Explanation:

Newton's Second Law of motion: It states that the rate of change of momentum is directly proportional to the applied force and takes places along the direction of the force.

It can be expressed mathematically as,

F ∝ m(v-u)/t

Where (v-u)/t = a

F = kma.

F = force, m = mass of the body, a = acceleration, k = constant of proportionality which tend to unity for a unit force, a unit mass, and a unit acceleration.

Therefore,

F = ma.

From the equation above,

If the net force acting on a body increase, while the mass of the body remains constant, the acceleration will also increase.

4 0

3 years ago

A metal rod 80cm long lengthens by 0.090cm when its temperature rises by 93.6$^o$C. What is the linear expansivity of the metal

alexandr1967 [171]

Answer: (b)0.000012/k

Explanation:

The linear expansion of the metal rod is given by

$\Delta L= L_0 \alpha \Delta T$

where

$\Delta L=0.090 cm$ is the linear expansion

$L_0 = 80 cm$ is the initial length of the rod

$\alpha$ is the linear expansivity

$\Delta T=93.6^{\circ}C=93.6 K$ is the increase in temperature

By re-arranging the equation, we find the linear expansivity:

$\alpha = \frac{\Delta L}{L_0 \Delta T}=\frac{0.090 cm}{(80 cm)(93.6K)}=0.000012 K^{-1}$

8 0

3 years ago

A proton is projected in the positive x direction into a region of a uniform electric field E S 5 126.00 3 105 2 i^ N/C at t 5 0

Dafna11 [192]

Answer:

(a). The magnitude of the acceleration of the proton is $5.74\times10^{13}\ m/s^2$

(b). The initial peed of the protion is $2.83\times10^{6}\ m/s$

(c). The time is $0.493\times10^{-7}\ sec$ .

Explanation:

Given that,

Electric field $E=-6.00\times10^{5}i\ N/C$

Time = 5.0 sec

Distance 7.00 cm

(a). We need to calculate the acceleration

Using formula of force

$F=F_{e}$

$ma=qE$

$a=\dfrac{Eq}{m}$

Where, E = electric field

m = mass of proton

q = charge of proton

Put the value into the formula

$a=\dfrac{-6.00\times10^{5}\times1.6\times10^{-19}}{1.67\times10^{-27}}$

$a=-5.74\times10^{13}\ m/s62$

The magnitude of the acceleration of the proton is $5.74\times10^{13}\ m/s^2$

(b). We need to calculate the initial peed

Using equation of motion

$v^2-u^2=2as$

Where, s = distance

Put the value into the formula

$0-u^2=2\times(-5.74\times10^{13})\times7.00\times10^{-2}$

$u=\sqrt{2\times5.74\times10^{13}\times7.00\times10^{-2}}$

$u=2834783.94$

$u=2.83\times10^{6}\ m/s$

The initial peed of the protion is $2.83\times10^{6}\ m/s$

(c). We need to calculate the time interval over which the proton comes to rest

Using formula

$t=\dfrac{u}{a}$

Where, u = initial velocity

a = acceleration

Put the value into the formula

$t=\dfrac{2.83\times10^{6}}{5.74\times10^{13}}$

$t=0.493\times10^{-7}\ sec$

Hence, (a). The magnitude of the acceleration of the proton is $5.74\times10^{13}\ m/s^2$

(b). The initial peed of the protion is $2.83\times10^{6}\ m/s$

(c). The time is $0.493\times10^{-7}\ sec$ .

5 0

3 years ago

A cheetah starts from rest and accelerates after a gazelle at a rate of 6.5 meters per second2for 3.0 seconds. Calculate the che

Pepsi [2]

Answer:

the speed of the cheetah at the end of the 3 seconds is: 19.5 m/s

Explanation:

Let's use the equation that relates speed with acceleration:

vf = vi + a * t

where vf stands for final velocity, vi stands for initial velocity, a for acceleration, and t for the time acceleration is applied. Then, in our case we have:

vf = 0 + 6.5 (3)

vf = 19.5 m/s

6 0

3 years ago

When energy is transformed, the amount of usable energy?

cricket20 [7]

Cannot be determined, I need more information.

7 0

3 years ago