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the tention at which a fishing line snaps is commomly called the line's "strenght" what minimum strength is
needed for a line that is stop a salmon of weight 85 N in 11 cm if the fish is initially drafting at 2.8 m/s?Assume a constant deceleration


A 500 kg rocket sled can be accelerated at a constant rate from rest to1600 km/h 1.8 s. what is the ؟magnitude of the required net force؟


Acar traveling at 53 lmh hits a bridge abutment a passenger in the car moves forward a distance of 65 cm (with respect to the road) while being brought to rest by an inflated air bag. wht magnitude of force(assumed constant) acts on the passenger's upper torso, which has a mass of 41 kg?

ولكم من الدعاء

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بسم الله الرحمن الرحيم

السلام عليكم ورحمة الله وبركاته

Question 1


First you have to find the acceleration

a = (vf² - vi²) / 2d

Where ,

vf² is the final velocity which is ZERO
vi² is the drifting speed

Now you get this equation

a = -vi²/2d

Second determine the force

F = m*a

m is the mass which = W * g , where W is the weight & g is the gravity acceleration which is 9.8 m/s²
a is the acceleration found in the first step

Just plug in the values and it is done.

you will have finally an equation like this

F = -(W/g) (vi²/2d)

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Question 2

The net force is given by F = m*a

find the acceleration

Use this equation

vf = vi + a*t , where vi is zero

Now it is easy find the acceleration then substitute it into the first equation of the net force.

Dont Forget To Convert The units into SI units.

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Question 3

Initial kinetic energy = (1/2)*m*vi²

Final kinetic energy = 0

Work done to dissolve this kinetic energy = F*d

Let

(1/2)*m*vi² = F*d

m is the mass given 41 Kg
vi is the initial velocity 53 Km/hr ( Convert it to m/s )
F is the force needed in this question
d is the distance moved by the car 65 cm ( Convert it to m )

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الله يسعدك في الدنيا والأخره حليت المسائل في وقتها لأن لازم أسلمها بكره

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