Velocity Q's (1 Viewer)

[nrumble42]

hey guys. I'm having trouble with this topic, so could you pls explain your steps as you go

the velocity of a particle is given by v=1/(15x^2) m/s and the particle is initially at the origin. find it's displacement after 4 seconds to 2.d.p

 

[1729]

hey guys. I'm having trouble with this topic, so could you pls explain your steps as you go

the velocity of a particle is given by v=1/(15x^2) m/s and the particle is initially at the origin. find it's displacement after 4 seconds to 2.d.p

 

[nrumble42]

I have another question i'm stuck on, so i thought i'd post it here as well

If a rocket's acceleration is given by a= -k/x^2, where x is the distance from the centre of the earth, and if the rocket starts from rest at the surface of the Earth (radius 6400km), find an equation for the velocity of the rocket in terms of x

 

[InteGrand]

I have another question i'm stuck on, so i thought i'd post it here as well

If a rocket's acceleration is given by a= -k/x^2, where x is the distance from the centre of the earth, and if the rocket starts from rest at the surface of the Earth (radius 6400km), find an equation for the velocity of the rocket in terms of x

Are you sure it starts at rest? If the rocket starts at rest on the surface of the earth, it's not going to move... (Unless you assume there's no ground or something.)

 

[nrumble42]

That's just what the question says, so I'm not sure tbh. the book has the answer as velocity = the square root of k(6400-x)/3200x