Projectiles (1 Viewer)

[johnle95]

An aeroplane flying horizontally at a height of 2000m with a velocity of 200m/s drops a bomb.
(a) Determine how long it takes the bomb to hit the ground.
(b) Find the horizontal distance travelled by the bomb.

please help
thanks

 

[HeroicPandas]

(a) They are telling u to find the time of flight

Time of flight:
When projectile strikes the ground, y = 0, solve for t

(b) They are telling u to find the range

Range:
Horizontal distance from origin to where the particle strikes the ground, so y = 0 (when the particle is at the ground it has no height), find t (time of flight) and sub t into ur x-horizontal equation and u get the range

Horizontal and vertical displacements of the particle
The plane is flying horizontally, so it's angle with the horizontal is 0
x'' = 0
x' = 200cos(0) = 200
x = 200t

y'' = -9.8
y' = -9.8t + 200sin(0) = -9.8t
y = -4.9t^2 + 2000

 

[johnle95]

(a) They are telling u to find the time of flight

Time of flight:
When projectile strikes the ground, y = 0, solve for t

(b) They are telling u to find the range

Range:
Horizontal distance from origin to where the particle strikes the ground, so y = 0 (when the particle is at the ground it has no height), find t (time of flight) and sub t into ur x-horizontal equation and u get the range

Horizontal and vertical displacements of the particle
The plane is flying horizontally, so it's angle with the horizontal is 0
x'' = 0
x' = 200cos(0) = 200
x = 200t

y'' = -9.8
y' = -9.8t + 200sin(0) = -9.8t
y = -4.9t^2 + 2000

what is the equation for y?

 

[johnle95]

i need help in this one as well

A projectile is fired with initial velocity Vm/s at an angle of projection theta, from a point 0 on horizontal ground.
After 1s, it just passes over a 12m high wall 20m from the point of projection.
(a) Find V and theta.
(b) Find the maximum height h reached by the projectile.
(c) Find the range R.

 

[HeroicPandas]

what is the equation for y?

read the last line of my post: y = -4.9t^2 + 2000

if u are looking for the trajectory, u dont need it

 

[HeroicPandas]

i need help in this one as well

A projectile is fired with initial velocity Vm/s at an angle of projection theta, from a point 0 on horizontal ground.
After 1s, it just passes over a 12m high wall 20m from the point of projection.
(a) Find V and theta.
(b) Find the maximum height h reached by the projectile.
(c) Find the range R.

Give me what u have gotten so far, i dont want to spoon-feed u, spoon-feeding in one of the most hardest 3U topics will not lead u to victory

 

[johnle95]

read the last line of my post: y = -4.9t^2 + 2000

if u are looking for the trajectory, u dont need it

where did u get 9.8 from for the gravitational acceleration?

 

[HeroicPandas]

where did u get 9.8 from for the gravitational acceleration?

the question usually does give u g = g/-9.8/-10, so since u gave me nothing on g, i'll assume its 9.8

 

[HeroicPandas]

here the diagram