Look at the graph below.

a Car with a mass of 2000 kg is moving around a circular curve at a uniform velocity of 25 m/s the curve has a radius of 80 m wh

Viefleur [7K]

Well, first of all, the car is not moving at a uniform velocity, because,
on a curved path, its direction is constantly changing. Its speed may
be constant, but its velocity isn't.

The centripetal force on a mass 'm' that keeps it on a circle with radius 'r' is

   F = (mass) · (speed)² / (radius).

For this particular car, the force is

(2,000 kg) · (25 m/s)² / (80 m)

   = (2,000 kg) · (625 m²/s²) / (80 m)

   = (2,000 · 625 / 80) (kg · m / s²)

   = 15,625 newtons .

5 0

4 years ago

Please Help:)<br> How to draw two vectors being added:

scoray [572]

Explanation:

you add the from head to tail. Head is the triangle and tail is the final point of the vector

4 0

3 years ago

The friends are ready to try a problem. A battery has an emf of 12.0 V and an internal resistance of 0.05 Ω. Its terminals are c

Zanzabum

Answer:

Terminal voltage = 11.5 V

Power across load = 119.7 W

Power across internal resistance = 5.4 W

Power delivered by battery = 125.2 W

Explanation:

The current in the circuit is given by

$I=\dfrac{E}{R+r}$

where E is the emf of the battery, R us the load resistance and r is the internal resistance.

$I=\dfrac{12}{1.1+0.05} = 10.43 \text{ A}$

The terminal voltage is the potential difference across the load resistor.

V = I × R = 10.43 A × 1.1 Ω = 11.5 V

The power across any resistance is given by $I^2R$

For the load resistor,

$P_L=10.43^2\times1.1 = 119.7 \text{ W}$

For the internal resistance,

$P_r=10.43^2\times0.05= 5.4\text{ W}$

The power delivered by the battery is

$P = P_L + P_r = 119.7 + 5.4 = 124.1 \text{ W}$

This could also be found by

$P = IE = 10.34\times12 = 125.2 \text{ W}$

The discrepancy in both answers is due to the approximations. The second answer is better.

4 0

4 years ago

A force of 825 N is needed to push a car across a parking lot. Two students push a car 35 m. How much total work is done?

MaRussiya [10]

<h2>Answer :</h2><h2 />

Work is the amount of energy transferred. As per the formula

Work = Force x Distance [moved toward the direction of the force]

So as per the formula

<u>Solution : </u>

Force = 825 N

Distance = 35 m

Work = 825 (n) x 35 (m)

Work = 28875 Joules

<h2 />

6 0

3 years ago

-What can you say about the snowboarder’s kinetic energy as he moves?

Damm [24]

Answer:

His kinetic energy increases, potential energy decreases

The sum of kinetic and potential energy is a constant at any instant before he comes to rest.

Explanation:

Snowboarder is starting from a height and moving to the down direction. As he moves down his velocity increases, we know that kinetic energy is given by the expression $\frac{1}{2} mv^2$ , so as he moves his kinetic energy increases.

When the snowboarder is starting his potential energy is maximum(Potential energy = mgh), as he comes down his potential energy decreases.

Based on this we can conclude that the sum of potential energy and kinetic energy is a constant at any instant for a snowboarder before he comes to rest.

mgh+ $\frac{1}{2} mv^2$ = Constant

7 0

4 years ago