How Do You Calculate Height Without Acceleration in Physics Problems?

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Calculating height without acceleration in physics problems can be challenging, especially when the gravitational acceleration (g) is not explicitly provided. Participants express difficulty in determining height due to potential miscalculations and insufficient data. The discussion emphasizes the importance of using the correct initial velocities, particularly distinguishing between vertical and horizontal components. There is a consensus that gravitational acceleration should be considered, and if not given, it may be derivable from other data. Clarifying the initial conditions and ensuring correct application of kinematic equations are crucial for solving the problem.
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Homework Statement
A bomb of mass 15.0 kg with an initial velocity of 350 m/s and horizontal velocity of 250 m/s is
projected from the edge of a cliff of a height 500 m. The kinetic energy just before it hits the target
is 500 kJ.
(a) Determine the initial kinetic energy of the bomb.
[2 Marks]
(b) Show the change of kinetic energy of the bomb.
[2 Mark]
(c) Find the value of the initial angle.
[2 Marks]
(d) Calculate the height of the target from the ground.
[4 Marks]
(e) Determine the kinetic energy and velocity at the height of 2.50 × 103 m from the
ground? [5 Marks]
Relevant Equations
v^2=u^2+2as
For parts (d) and (e) I can't figure out the required steps to get the height due to the fact that I don't have the acceleration. I may have done a miscalculation for the former questions as well. I also feel (e) requires the value of a. Hope someone can help me out. Been going at this question for 2 days now.
 
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Isn't the movement of the bomb inside the gravitational field of earth?
Isn't the gravitational acceleration of earth, g, given by the problem?

If g is not given by the problem data, then we should be able to find it from other given data, but i am afraid the given data is not enough to find g.
 
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Delta2 said:
Isn't the movement of the bomb inside the gravitational field of earth?
Isn't the gravitational acceleration of earth, g, given by the problem?

If g is not given by the problem data, then we should be able to find it from other given data, but i am afraid the given data is not enough to find g.
That is what I thought as well initially. If i use 9.81 as the value of a in a kinematic eq, I still can't find the height of the target from the ground. I just end up with a value that proves the target is not lifted off the ground at all
 
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Hmmm you got to show us your workings, but let me ask this do you get a negative value for the height of the target?
 
Har2803 said:
initial velocity of 350 m/s and horizontal velocity of 250 m/s
Something missing? Should that be initial vertical velocity of 350 m/s (up or down?) or perhaps initial speed?
 

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