A box is 30cm wide , 50cm long and 20cm high Calculate :

Two skiers arrive at the bottom of a ramp travelling at the same speed. Friction may be ignored in this problem. One skier is an

inysia [295]

Answer:

Both will reach to same height

Explanation:

Here we can see that friction is to be ignored

so we can say that work done by all the non conservative forces is change in mechanical energy

Since all non conservative forces here is zero

so mechanical energy is conserved here

so here we can say that sum of initial kinetic energy and potential energy = sum of final kinetic energy and potential energy

So we will have

$\frac{1}{2}mv^2 = mgH$

now maximum height is given as

$H = \frac{v^2}{2g}$

so here we can say that greatest height will be independent of the mass so they both will reach at same height

6 0

3 years ago

Ruby is out with her friends. Misfortune occurs and

zhannawk [14.2K]

The work done is $2.35\cdot 10^5 J$

Explanation:

The work done by a force on an object is given by:

$W=Fd cos \theta$

where

F is the magnitude of the force

d is the displacement of the object

$\theta$ is the angle between the direction of the force and of the displacement

In this problem, we have

F = 1080 N is the force applied on the car

d = 218 m is the displacement of the car

And assuming the force is applied parallel to the motion of the car, $\theta=0^{\circ}$ , and so the work done is

$W=(1080)(218)(cos 0^{\circ})=2.35\cdot 10^5 J$

Learn more about work:

brainly.com/question/6763771

brainly.com/question/6443626

#LearnwithBrainly

3 0

3 years ago

4. A car accelerates, from rest, at 2.4 m/s?. How fast is the car traveling

pantera1 [17]

Answer:

19.2m/s

Explanation:

Assuming that 2.4m/s^2 was the acceleration and not a typo, we can use the equation v=at, where v=velocity, a=acceleration, and t=time,

plug in known varibles,

v=2.4*8

v=19.2m/s

4 0

2 years ago

According to the second law of thermodynamics, which is a requirement for thermal energy to flow from colder objects to hotter o

maxonik [38]

Answer: work must be done on the system (Option A)

Explanation:

The second law of thermodynamics is the fundamental law of nature; it states that energy can be transferred from cold objects to hot objects only, if work is done on the system. If energy is added to the system then as a result the thermal energy would increase. Second law of thermodynamics is used to determine whether a process is spontaneous or not. Moreover,the second law of thermodynamics is also used in refrigerators.

4 0

3 years ago

Read 2 more answers

a 150 N force is used to pull a wooden box across a wooden surface at a constant velocity. what is the mass of the box?

IRINA_888 [86]

Answer:

The mass of the box:

m = 60 kg

Explanation:

Given:

F = 150 N

g = 10 m/s²

_________

m - ?

Coefficient of friction wood on wood:

μ = 0.25

Friction force:

F₁ = μ*m*g

Newton's Third Law:

F = F₁

F = μ*m*g

The mass of the box:

m = F / ( μ*g) = 150 / (0.25*10) = 60 kg

7 0

1 year ago