All categories

3 years ago

4. A train is travelling at a speed of 60 km/ h. Brakes are applied so as to produce a uniform

Physics

1 answer:

maxonik [38]3 years ago

7 0

Answer:

33.33 m

Explanation:

Applying Newton's equation of motion,

v² = u²+2as...................... Equation 1

Where v = final velocity of the train, u = initial velocity of the train, a = acceleration of the train, s = distance.

make s the subject of the equation

s = (v²-u²)/2a................ Equation 2

Given: v = 0 m/s ( brought to rest), u = 60 km/h = 60(1000/3600) m/s = 16.67 m/s, a = -0.5 m/s²

Substitute this values into equation 2

s = (0-16.67)/-0.5

s = -16.67/-0.5

s = 33.33 m

You might be interested in

When summer changes to fall, what seasonal changes do plants experience? (IGNORE HIGHLIGHTED ANSWER)

lorasvet [3.4K]

Answer:

Explanation:

There is a decrease in temperature and daylight and plants produce less food.

Please mark brainliest!!

*Quick Reminder: If this is an assignment from homeschool/school, please don't forget to rephrase/summarize/reference from this answer. Keep in mind no plagiarism is allowed in school. And please don't plagiarize this answer. Thanks!*

7 0

2 years ago

suppose that a large cargo truck needs to cross a bridge. the truck is 30 m long and 3.2 m wide. the cargo exerts a force nof 54

Tamiku [17]

<span>No, because the truck applies more pressure than the bridge can support.</span>

7 0

2 years ago

A ball with 100 J of PE is released from a height of 10 m. What will be the KE of the ball at 5

harkovskaia [24]

Answer:

The kinetic energy is: 50[J]

Explanation:

The ball is having a potential energy of 100 [J], therefore

PE = [J]

The elevation is 10 [m], and at this point the ball is having only potential energy, the kinetic energy is zero.

$E_{p} =m*g*h\\where:\\g= gravity[m/s^{2} ]\\m = mass [kg]\\m= \frac{E_{p} }{g*h}\\ m= \frac{100}{9.81*10}\\\\m= 1.01[kg]\\\\$

In the moment when the ball starts to fall, it will lose potential energy and the potential energy will be transforme in kinetic energy.

When the elevation is 5 [m], we have a potential energy of

$P_{e} =m*g*h\\P_{e} =1.01*9.81*5\\\\P_{e} = 50 [J]\\$

This energy is equal to the kinetic energy, therefore

Ke= 50 [J]

8 0

3 years ago

a 2.35 water bucket is swung in a full cirlce of radius 0.824 m just fast enough so that the water doesn't fall out the top mean

tiny-mole [99]

Answer:

2.84 m/s

Explanation:

At the top position of the circular trajectory, the normal reaction is zero:

N = 0

So it means that the only force that is providing the centripetal force is the gravitational force (the weight of the bucket). Therefore we have:

$mg = m \frac{v^2}{r}$

where

m is the mass of the water bucket

g = 9.8 m/s^2 is the acceleration of gravity

v is the speed of the bucket

r = 0.824 m is the radius of the circle

Solving for v,

$v=\sqrt{gr}=\sqrt{(9.8 m/s^2)(0.824 m)}=2.84 m/s$

4 0

3 years ago

When a falling object reaches terminal velocity, the net force acting on it is

dexar [7]

Pretty sure that it is 0.

3 0

3 years ago