Identify the kind of simple machine represented by each of these examples: a. A drill bit b. A skateboard ramp c. A boat oar

You pull your little sister across a flat snowy field on a sled. Your sister plus the sled have a mass of 22 kg. The rope is at

kati45 [8]

Answer:

Explanation:

mass of sled, m = 22 kg

Force of pull, F = 31 N

distance move, d = 53 m

Angle between force and distance, θ = 40°

The formula for the work done is

W = F x d x Cos θ

W = 31 x 53 x cos 40

W = 1258.6 J

7 0

3 years ago

Which of the following describes a risk associated with the use of hydropower as an energy source?

castortr0y [4]

Its A: the use of hydropower often changes the natural flow of water through an ecosystem

add me on robloxs

5 0

3 years ago

Which nuclei is not radioactive? A. Am-241 B. Mg-24 C. Pu-241 D. U-238

Helen [10]

Hello!

Which nuclei is NOT radioactive?

A) Am-241 B) Mg-24 C) Pu-241 D) U-238

Solving:

It is noteworthy that chemical elements located on the periodic table in the lanthanide and actinide groups are radioactive.

Am-241 (americium) belongs to the group of actinides and is a heavy and radioactive metal.

Mg-24 (magnesium) is an essential element for the body, mainly for the nervous system, in addition to synthesizing proteins and serves for hormonal control, belongs to the group of alkaline earth metals and is a non-radioactive nucleus.

Pu-241 (plutonium) is an element that is isotope of fission by plutonium, belongs to the group of actinides and is a heavy and radioactive metal.

U-238 (uranium) is an element that is isotope of non-fission uranium, belongs to the group of actinides and is a heavy and radioactive metal.

Answer:

B) Mg-24

_______________________

I Hope this helps, greetings ... Dexteright02! =)

6 0

3 years ago

Two boats start together and race across a 48-km-wide lake and back. Boat A goes across at 48 km/h and returns at 48 km/h. Boat

nika2105 [10]

Answer:

Part 1)

Boat A will win the race

Part 2)

Boat A will win the race by 48 km as the 2nd boat will reach the other end while boat A will just touches the finish line

Part 3)

average velocity must be zero

Explanation:

As we know that the distance moved by the boat is given as

$d = 48 km$

now the time taken by the boat to move to and fro is given as

$t = \frac{d}{v}$

$t = \frac{48 + 48}{48}$

$t = 2 hrs$

Time taken by Boat B to cover the distance

$t = \frac{48}{24} + \frac{48}{72}$

$t = 2.66 h$

Part 1)

Boat A will win the race

Part 2)

Boat A will win the race by 48 km as the 2nd boat will reach the other end while boat A will just touches the finish line

Part 3)

Since the displacement of Boat A is zero

so average velocity must be zero

3 0

3 years ago

hii! i need answers for both of these! this is due tomorrow and i want to get it done so i can finish all my other work, thank y

d1i1m1o1n [39]

Answer:

The mass and velocity for kinetic energy. Potential Energy: How high an object is and the mass in kilograms or it is the weight in and how high an object is. There are two formulas to calculate potential energy, but the one with grams is used more often.

Explanation:

Hope this helps!

5 0

3 years ago