Chapter 07, Problem 050 Your answer is partially correct. Try again. (a) At a ce

Question

Chapter 07, Problem 050 Your answer is partially correct. Try again. (a) At a certain instant, a particle-like object is acted on by a force F (4.20 N)i (3.90 N)j+(7.90 N )k while the object's velocity is v = -( 1. 10 m/s )1+ (3.80 m/s ) k . What is the instantaneous rate at which the force does work on the object? (b) At some other time, the velocity consists of only a y component. If the force is unchanged, and the instantaneous power is -19.0 W, what is the velocity of the object just then? (Give your answer without a unit vector.) (a) Numbe 25.4 (b) Number 17.04 Unitstw UnitsT m/s

Explanation / Answer

b) let v = vy j

we know,

Rate of workdone = F.v

-19 = (4.2 i - 3.9 j + 7.9 k).(vy j)

-19 = -3.9*vy

==> vy = 19/3.9

= 4.87 m/s

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

---

---

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