1 ENT ES Chapter 04, Problem 101 on Concepts on 15 on Concents on 24 r 04. Probl

Question

1 ENT ES Chapter 04, Problem 101 on Concepts on 15 on Concents on 24 r 04. Problem A 2.56 x 10-kg tunar landing craft is about to touch down on the surface of the moon, where the acceleration due to gravity is 1.60 m/s2. At an altitude of 289 m the craft's downward velocity is 16.5 m/s. To slow down the craft, a retrorocket is firing to provide an upward thrust. Assuming the descent is vertical, find the magnitude of the thrust needed to reduce the velocity to zero at the instant when the craft touches the lunar surface. 04. Problem

Explanation / Answer

Applying vf^2 - vi^2 = 2 a d

0^2 - 16.5^2 = 2 ( a) (289)

a = - 0.471 m/s^2  

acceleration will be in opposite direction of velocity.

v-> donward

a -> upward  

Applying Fnet = m a

F - m g = m a

F = (2.56 x 10^4) (1.60 + 0.471)

F = 5.30 x 10^4 N ....Ans

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.