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How does an inclined plane change distance and how does it change direction

ElenaW [278]

Objects are known to go down because of a unbalanced force

7 0

3 years ago

An undiscovered planet, many light-years from Earth, has one moon, which has a nearly circular periodic orbit. If the distance f

EleoNora [17]

Answer:

364days

Explanation:

Pls see attached file

Explanation:

8 0

4 years ago

A 500 kg dragster accelerates from rest to a final speed of 100 m/s in 400 m (about a quarter of a mile) and encounters an avera

Fantom [35]

In order to accelerate the dragster at a speed $v_f = 100 m/s$ , its engine must do a work equal to the increase in kinetic energy of the dragster. Since it starts from rest, the initial kinetic energy is zero, so the work done by the engine to accelerate the dragster to 100 m/s is
$W= K_f - K_i = K_f = \frac{1}{2}mv_f^2=2.5 \cdot 10^6 J$

however, we must take into account also the fact that there is a frictional force doing work against the dragster, and the work done by the frictional force is:
$W_f = F_f d = -(1200 N)(400 m)= -4.8 \cdot 10^5 J$
and the sign is negative because the frictional force acts against the direction of motion of the dragster.

This means that the total work done by the dragster engine is equal to the work done to accelerate the dragster plus the energy lost because of the frictional force, which is $-W_f$ :
$W_t = W + (-W_f)=2.5 \cdot 10^6 J+4.8 \cdot 10^5 J=2.98 \cdot 10^6 J$

So, the power delivered by the engine is the total work divided by the time, t=7.30 s:
$P= \frac{W}{t}= \frac{2.98 \cdot 10^6 J}{7.30 s}=4.08 \cdot 10^6 W$

And since 1 horsepower is equal to 746 W, we can rewrite the power as
$P=4.08 \cdot 10^6 W \cdot \frac{1 hp}{746 W} =547 hp$

3 0

4 years ago

Read 2 more answers

A 5.6 cm diameter parallel-plate capacitor has a 0.58 mm gap. What is the displacement current in the capacitor if the potential

BARSIC [14]

Answer:

$1.88\cdot 10^{-5} A$

Explanation:

The capacitance of a parallel plate capacitor is given by:

$C=\frac{\epsilon_0 A}{d}$ (1)

where

$\epsilon_0$ is the vacuum permittivity

A is the area of the plates

d is the separation between the plates

The charge stored on the capacitor is given by

$Q=CV$ (2)

where C is the capacitance and V is the voltage across the capacitor.

The displacement current in the capacitor is given by

$J=\frac{Q}{t}$ (3)

where t is the time elapsed

Substituting (1) and (2) into (3), we find an expression for the displacement current:

$J=\frac{CV}{t}=\frac{\epsilon_0 A}{d} \frac{V}{t}$

where we have

$A=\pi (\frac{d}{2})^2=\pi (\frac{0.056 m}{2})^2=2.46\cdot 10^{-3} m^2$

$d = 0.58 mm = 5.8\cdot 10^{-4} m$

$\frac{V}{t}=500,000 V/s$

Substituting into the equation, we find

$J=\frac{(8.85\cdot 10^{-12} F/m)(2.46\cdot 10^{-3} m^2)}{5.8\cdot 10^{-4}m}(500,000 V/s)=1.88\cdot 10^{-5} A$

6 0

3 years ago

How do you think speed affects car and driver safety?

blondinia [14]

An increase in average speed of 1 km/h typi- cally results in a 3% higher risk of a crash involving injury, with a 4–5% increase for crashes that result in fatalities. — Speed also contributes to the severity of the impact when a collision does occur. Hope this helps!

4 0

3 years ago