Help!!! Need answer ASAP.

a 2kg ball moving at speed 5m/s hits a wall .the force exerted by the wall on the ball is 100n .if the collision is perfectly el

levacccp [35]

Answer:

0.2s

force = change in momentum/ time

time = change in momentum/time

Explanation:

first, let's find the change in momentum

pf-pi

5×(-2) - 5× 2

-20kgm/s = 20kgm/s(by changing the direction of whole system)

time = change in momentum/time

20/100

0.2s

4 0

3 years ago

Assuming that voltage remains constant, what happens to the current in a filament if it is replaced by a longer wire?

Elena L [17]

Answer:

Choice B: The current decreases.

Explanation:

The resistance of a conductor is proportional to its length when radius and resistivity stays the same. The resistance of the longer filament will be greater than the resistance of the initial one.

For Ohmic conductors,

$\displaystyle I = \frac{V}{R}$ ,

where

$I$ is the current through the conductor,
$V$ is the voltage across the conductor, and
$R$ is the resistance of the conductor.

Voltage here stays the same. Increasing the resistance $R$ of the conductor will reduce the current.

The filament might heat up over time. The filament might not be an ohmic conductor. Still, a similar trend shall exist. Resistance will be greater in the longer filament, and current will decrease.

4 0

4 years ago

Read 2 more answers

Who was the first man to go into the orbit?

kkurt [141]

D. Yuri Gagarin

(Typing this to circumnavigate the 20 character minimum requirement)

4 0

4 years ago

5. One electrical appliance operates with a voltage of 120 V, while another operates with 240 V. Based on this information alone

serious [3.7K]

Answer:

Yes it is true saying that 2nd applience use more power than first one

4 0

3 years ago

Three dogs (Spot, Fido, and Steinberg) are pulling on a chew toy. The chew toy is experiencing no acceleration. Spot is pulling

quester [9]

Answer:

The magnitude and direction of the force applied by Steinberg are approximately 15.192 newtons and 126.704º.

Explanation:

The chew toy is at equilibrium and experimenting three forces from three distinct dogs. The Free Body Diagram depicting the system is attached below. By Newton's Laws we construct the following equations of equilibrium: (Sp is for Spot, F is for Fido and St is for Steinberg) All forces and angles are measured in newtons and sexagesimal degrees, respectively:

$\Sigma F_{x} = F_{F}\cdot \cos \theta_{F} + F_{St,x} = 0$ (1)

$\Sigma F_{y} = F_{F}\cdot \sin \theta_{F}-F_{Sp}+F_{St,y} = 0$ (2)

If we know that $F_{F} = 20\,N$ , $F_{Sp} = 30\,N$ and $\theta_{F} = 63^{\circ}$ , then the components of the force done by Steinberg on the chewing toy is:

$F_{St,x} = -F_{F}\cdot \cos \theta_{F}$

$F_{St,x} = -(20\,N)\cdot \cos 63^{\circ}$

$F_{St, x} = -9.080\,N$

$F_{St,y} = F_{Sp}-F_{F}\cdot \sin \theta_{F}$

$F_{St,y} = 30\,N-(20\,N)\cdot \sin 63^{\circ}$

$F_{St, y} = 12.180\,N$

The magnitud of the force is determined by Pythagorean Theorem:

$F_{St} = \sqrt{F_{St,x}^{2}+F_{St,y}^{2}}$

$F_{St} =\sqrt{(-9.080\,N)^{2}+(12.180\,N)^{2}}$

$F_{St} \approx 15.192\,N$

Since the direction of this force is in the 3rd Quadrant on Cartesian plane, we determine the direction of the force with respect to the eastern semiaxis:

$\theta_{St} = 180^{\circ} + \tan^{-1} \left(\frac{F_{St,y}}{F_{St,x}}\right)$

$\theta_{St} = 180^{\circ} + \tan^{-1} \left(\frac{12.180\,N}{-9.080\,N}\right)$

$\theta_{St} \approx 126.704^{\circ}$

The magnitude and direction of the force applied by Steinberg are approximately 15.192 newtons and 126.704º.

5 0

3 years ago