1. ________________electricity is the type of electricity commonly used in homes and businesses throughout the world.

A man wishes to pull a crate 15m across a rough floor by exerting a force of 100 N. The

Darina [25.2K]

Answer:

option (E) is correct.

Explanation:

Work done is defined as the product of force and the distance in the direction of force.

force, f = 100 N

Coefficient of friction, = 0.25

distance = 15 m

So, net force F = f - friction force

F = 100 - 0.25 x m g

Work = (100 - 0.25 mg) x d cosθ

For minimum work, the angle should be maximum.

So, the value of θ is 76°.

thus, option (E) is correct.

3 0

3 years ago

How many protons, electrons and nurturing does krypton have NEED HELP ASAP THANK YOU

Assoli18 [71]

Answer:

Krypton – Mass Number – Neutron Number – Kr 2020-11-21 by Nick Connor Krypton is a chemical element with atomic number 36 which means there are 36 protons and 36 electrons in the atomic structure. The chemical symbol for Krypton is Kr.

Atomic Number: 36

Element: Krypton

Element Category: Noble Gas

Symbol: Kr

Explanation:

8 0

2 years ago

Read 2 more answers

The maximum oxygen uptake is known as the

grandymaker [24]

<span>The maximum oxygen uptake is known as the VO max.</span>

3 0

3 years ago

You observe that a mass suspended by a spring takes 0.25 s to make a full oscillation. What is the frequency of this oscillation

Katarina [22]

Answer:

Frequency of oscillation, f = 4 Hz

time period, T = 0.25 s

Angular frequency, $\omega = 25.13 rad/s$

Given:

Time taken to make one oscillation, T = 0.25 s

Solution:

Frequency, f of oscillation is given as the reciprocal of time taken for one oscillation and is given by:

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

f = $\frac{1}{0.25}$

Frequency of oscillation, f = 4 Hz

The period of oscillation can be defined as the time taken by the suspended mass for completion of one oscillation.

Therefore, time period, T = 0.25 s

Angular frequency of oscillation is given by:

$\omega = 2\pi \times f$

$\omega = 2\pi \times 4$

$\omega = 25.13 rad/s$

5 0

3 years ago

A bicycle wheel of radius 0.70 m is rolling without slipping on a horizontal surface with an angular speed of 2.0 rev/s when the

aleksandrvk [35]

Answer:

θ= 5 radian

Explanation:

Given data:

Radius r = 0.70 m

Initial angular speed ω_i = 2rev/s

Time t = 5 s

Final angular speed ω_f =0

so we have angular displacement

$\theta= \frac{\omega_f-\omega_i}{2}\times t$

putting values

$\theta= \frac{0-2}{2}\times5$ = 5 rad

8 0

3 years ago