All categories

3 years ago

URGENT HELP PLS

Physics

1 answer:

sergey [27]3 years ago

4 0

Explanation:

work done is equals to force into displacement in the direction of force

Ans: D

You might be interested in

If a student leaves 100-w lightbulb on In his room for 1 h, how many kilowatt-hour of electricity does the bulb use?

Anettt [7]

1) 0.1 kWh

Explanation:

The power of the lightbulb is:

$P = 100 W=0.1 kW$

The energy used by the lightbulb is equal to the product between the power (P) and the time (t):

$E=Pt$

Since the bulb has been left on for t = 1 h, the total electrical energy used is

$E=Pt=(0.1 kW)(1 h)=0.1 kWh$

2) $ 0.018

Explanation:

The company charges $0.18 per each kilowatt-hour. So, we can find the total cost charged for using 0.1 kWh of electricity by setting the following proportion:

$0.18 : 1 kWh = x : 0.1 kWh

And solving for x, we find

$x=\frac{\$0.18 \cdot 0.1kWh}{1 kWh}=\$ 0.018$

4 0

3 years ago

A softball is fouled off with a vertical velocity of 20 m/s and a horizontal velocity of 15 m/s. what is the resultant velocity

Kruka [31]

25 m/s is the answer

6 0

3 years ago

Which statement is TRUE?

Salsk061 [2.6K]

Statement B is true.

3 0

4 years ago

Read 2 more answers

What is the period of a wave with a frequency of 100 Hz and a wavelength of 2.0 m

spin [16.1K]

The answer for the following answer is answered below.

Therefore the time period of the wave is 0.01 seconds.
Therefore the option for the answer is "B".

Explanation:

Frequency (f):

The number of waves that pass a fixed place in a given amount of time.

The SI unit of frequency is Hertz (Hz)

Time period (T):

The time taken for one complete cycle of vibration to pass a given point.

The SI unit of time period is seconds (s)

Given:

frequency (f) = 100 Hz

wavelength (λ) = 2.0 m

To calculate:

Time period (T)

We know;

According to the formula;

f = $\frac{1}{T}$

Where,

f represents the frequency

T represents the time period

from the formula;

T = $\frac{1}{f}$

T = $\frac{1}{100}$

T = 0.01 seconds

Therefore the time period of the wave is 0.01 seconds.

5 0

3 years ago

Read 2 more answers

A 15.5 kg block is pulled by two forces. The first is 11.8N at a 53.7 angle and the second is 22.9 N at a -15.8 angle. What is t

anygoal [31]

Answer:

α = 6.43° (Angle respect to the horizontal axis-x)

Explanation:

To solve this problem we must use Newton's second law which tells us that the sum of forces must be equal to the product of mass by acceleration.

Since we have two forces and we know their magnitudes and their directions, we can sum these into their X & y components, in this way we can find the resulting force and apply it in Newton's second law.

F1x = 11.8*cos(53.7) = 6.98 [N]

F1y = 11.8*sin(53.7) = 9.5 [N]

Now with the second force:

F2x = 22.9*cos (15.8) = 22.03 [N]

F2y = - 22.9*sin (15.8) = - 6.23 [N]

Now we sum the forces in the x and y axes:

Fx = F1x + F2x = 6.98 + 22.03 = 29.01 [N]

Fy = F1y + F2y = 9.5 - 6.23 = 3.27 [N]

Now using the Pythagorean theorem we can find the resulting force.

F = √(Fx² + Fy²)

F = √ (29.01)² + (3.27)²

F = 29.19 [N]

Using Newton's second law, we have:

F = m*a

where:

F = force = 29.19 [N]

m = mass = 15.5 [kg]

a = acceleration [m/s²]

a = 29.19/15.5

a = 1.88 [m/s²]

The direction of the acceleration is the same direction of the force, therefore we need to find the angle.

tan(α) = Fy/Fx

tan(α) = 3.27/29.01

α = tan⁻¹(0.1127)

α = 6.43° (Angle respect to the horizontal axis-x)

3 0

3 years ago