Motion in a Plane: Projectile Hits Ground 7.5s Later

In summary, a projectile is launched with an initial speed of 30m/s at an angle of 60° above the horizontal. It hits the ground 7.5s later. Using the equations of motion, it can be determined that the launch point is 12.45° above the point where the projectile hits the ground. The vertical displacement, y, is zero at the point of impact.
  • #1
Lydia22
33
0

Homework Statement



A projectile is fired with an initial speed of 30m/s at an angle of 60° above the horizontal.The object hits the ground 7.5s later.
a)How much higher or lower is the launch point relative to the point where the projectile hits the ground?

Homework Equations





The Attempt at a Solution


a)u(y)=30sin60,u(x)=30cos60
v=u+at
=30sin60-9.8*7.5
=47.52 downwards
tanθ=V(y)/V(x)
=(-47.53/30cos60)
=72.48° below the x-axis
therefore,the launch point is 72.48°-60°=12.45° above relative to the point where the projectile hits the ground.
 
Physics news on Phys.org
  • #2
The vertical displacement, y, is the point where the projectile hits the ground.
 
  • #3
Isn't the vertical displacement zero?
 

FAQ: Motion in a Plane: Projectile Hits Ground 7.5s Later

1. What is "Motion in a Plane"?

Motion in a plane refers to the movement of an object in two dimensions, typically represented by x and y coordinates. It takes into account both the horizontal and vertical components of an object's motion.

2. What is a projectile?

A projectile is any object that is launched into the air and moves under the influence of gravity. Examples of projectiles include a ball thrown into the air, a bullet fired from a gun, or a rock thrown from a cliff.

3. How does a projectile hit the ground?

A projectile hits the ground when it reaches its maximum height and begins to fall back down due to the force of gravity. The time it takes for a projectile to hit the ground depends on its initial velocity, angle of launch, and the force of gravity.

4. What is the significance of a projectile hitting the ground 7.5 seconds later?

The time it takes for a projectile to hit the ground is important because it can help us calculate its initial velocity or angle of launch. In the case of a projectile hitting the ground 7.5 seconds later, we can use this information to solve for other variables in its motion, such as its maximum height or range.

5. How is the motion of a projectile in a plane different from motion in a straight line?

The main difference between motion in a plane and motion in a straight line is that motion in a plane involves both horizontal and vertical components, while motion in a straight line only involves movement along one axis. This means that the path of a projectile will be curved rather than straight, due to the influence of gravity.

Similar threads

Projectile Motion - object that is shot at an angle of 55 degrees
Replies
8
Views
2K
Calculate the displacement? (Projectile motion problem)
Replies
3
Views
2K
Projectile Motion: time it takes for projectile to hit truck
Replies
15
Views
2K
Projectile Motion -- Help please understanding these basic problems
Replies
4
Views
1K
Projectile motion of a cannon ball versus time
Replies
15
Views
2K
Where on the hill does the projectile land?
Replies
9
Views
3K
Projectile hitting the incline plane horizontally
Replies
7
Views
4K
Projectile motion above ground given only angle and height
Replies
3
Views
2K
Projectile Motion: initial velocity problem
Replies
1
Views
1K
Hitting a rocket with a projectile
2
Replies
53
Views
4K

Hot Threads

Recent Insights

Back
Top