Ask question

Ask question

All categories

3 years ago

6

find the rate of positive acceleration of an automobile which went from a complete stop to a velocity of 30 meters per second in

10 seconds

1 answer:

maks197457 [2]3 years ago

3 0

Answer:

3 m/s^2

Explanation:

acceleration= Change in velocity/time

= 30-0 / 10

= 30/10

=3 m/s^2

You might be interested in

in a circuit, where do electric charges go once they have left the voltage source and traveled along the wires?

S_A_V [24]

In an electric circuit, the free electrons are moving around. Since equal charges repel and opposite charges attract, the electrons move from the negatively charged to the positively charged pole of the voltage source.

7 0

3 years ago

If a constant force of 20N is applied to a cart, how much power does the force exert on the cart when it reaches a speed of 4m/s

SCORPION-xisa [38]

Answer:80watts

Explanation:

Power=force×velocity

Power=20×4

Power=80watts

3 0

3 years ago

Heater supplies 80 J of energy to a block of metal. The temperature of the block rises by 20 °C.

Grace [21]

Answer:

Its internal energy decreases by 40 J.

Explanation:

The energy supplied to the metal block causes the temperature of the block to rise. Therefore,

$Heat\ Supplied = mC\Delta T\\80\ J = mC(20^oC)\\mC = 4\ J/^oC\\$

Now, we will use this value of mC to find out the energy change of block:

$Energy\ Change = mC\Delta T\\Energy\ Change = (4\ J/^oC)(-10^oC)\\Energy\ Change = -40J\\$

It shows that when the temperature of the metal block falls by 10°C,

<u>Its internal energy decreases by 40 J.</u>

5 0

3 years ago

Suppose your grocery cart is moving at a constant momentum in a straight line down the aisle of a store, without friction. How w

Strike441 [17]

Answer:

It will increase

Explanation:

The kinetic energy is the energy possessed by a moving object and is given by:

KE = $1/2 mv^2$

where m = mass of the object and v = velocity of the object.

It does means that the more the mass of an object in motion, the more the kinetic energy of the object if there are no opposing force such as friction. Also, the more the kinetic energy of the object, the more the speed of that object.

<em>Hence, as the weight of the cart increases by addition of groceries, the kinetic energy increases and the speed also increases as it moves along the frictionless surface.</em>

7 0

3 years ago

If a 200 turn, 10-3 m2 cross-sectional area coil is immersed in a magnetic field such that the plane of the coil is perpendicula

Stels [109]

Answer:

<h3>1.2 volt induced in coil.</h3>

Explanation:

Given:

Number of turns $N = 200$

Cross sectional area $A = 10^{-3}$ $m^{2}$

Rate of increasing magnetic field $\frac{dB}{dt} = 6$ $\frac{T}{s}$

From the faraday's law,

Induced emf is given by,

$\epsilon = -N\frac{d \phi}{dt }$

Where $\phi =$ magnetic flux

$\phi = AdB \cos(0)$ ( because angle between normal coil and field is zero)

Where $A =$ area of coil

Put the value of $\phi$ in above equation,

Here we neglect minus sign

$\epsilon = NA\frac{dB}{dt}$

$\epsilon = 200 \times 10^{-3} \times 6$

$\epsilon = 1.2$ V

Therefore, 1.2 volt induced in coil

8 0

3 years ago