20 points!!

If there were no dark energy in the universe, the value of __________ would solely determine the evolution and fate of the unive

Talja [164]

Answer:

Ωmass

Explanation:

If there were no dark energy in the universe, the value of Ωmass would determine the evolution and fate of the universe.

5 0

3 years ago

1) A net force of 75.5 N is applied horizontally to slide a 225 kg crate across the floor.

dimulka [17.4K]

Answer:

The acceleration of the crate is $0.3356\,\frac{m}{s^2}$

Explanation:

Recall the formula that relates force,mass and acceleration from newton's second law;

$F=m\,a$

Then in our case, we know the force applied and we know the mass of the crate, so we can solve for the acceleration as shown below:

$F=m\,a\\75.5\,N=225\,\,kg\,\,a\\a=\frac{75.5}{225} \,\frac{m}{s^2} \\a=0.3356\,\,\frac{m}{s^2}$

7 0

3 years ago

the momentum of a spring coil when the external compressing force is removed b the difference between the final momentum and the

Fed [463]

Answer:

the correct one is b

the difference between the final moment and the initial moment

Explanation:

The momentum is related to the moment

I = ΔP

∫ F dt = p_f - p₀

where p_f and p₀ are the final and initial moments, respectively

When checking the different answers, the correct one is b

the difference between the final moment and the initial moment

7 0

3 years ago

The average mass of a rhinoceros calf is 45 kg. What is its weight in newtons? Round your answer to the nearest whole number. 5

Thepotemich [5.8K]

Answer:

441 [N].

Explanation:

Weight=mass*g, where mass=45; g=9,8.

Weight=45*9.8=441 [N].

3 0

3 years ago

Read 2 more answers

A 60kg bicyclist (including the bicycle) is pedaling to the

Fittoniya [83]

a) 4 forces

b) 186 N

c) 246 N

Explanation:

a)

Let's count the forces acting on the bicylist:

1) Weight ( $W=mg$ ): this is the gravitational force exerted on the bicyclist by the Earth, which pulls the bicyclist towards the Earth's centre; so, this force acts downward (m = mass of the bicyclist, g = acceleration due to gravity)

2) Normal reaction (N): this is the reaction force exerted by the road on the bicyclist. This force acts vertically upward, and it balances the weight, so its magnitude is equal to the weight of the bicyclist, and its direction is opposite

3) Applied force ( $F_A$ ): this is the force exerted by the bicylicist to push the bike forward. Its direction is forward

4) Air drag ( $R$ ): this is the force exerted by the air on the bicyclist and resisting the motion of the bike; its direction is opposite to the motion of the bike, so it is in the backward direction

So, we have 4 forces in total.

b)

Here we can find the net force on the bicyclist by using Newton's second law of motion, which states that the net force acting on a body is equal to the product between the mass of the body and its acceleration:

$F_{net}=ma$