Ask Singapore Homework?
Upload a photo of a Singapore homework and someone will email you the solution for free.
Question
secondary 3 | E Maths
One Answer Below
Anyone can contribute an answer, even non-tutors.
Hi! I need help for this question, thank you for helping :)
Date Posted: 4 years ago
Views: 207
(a)
at start, ball at top of building
=> t = 0
h = 50+10t-5t² = 50
height = 50m
(b)
at top of building again,
=> 50+10t-5t² = 50
=> 5t² - 10t = 0
=> t(t - 10) = 0
=> t = 0 or t = 10 s
at t = 10 s
(c)
reach ground => h = 0 m
=> 50+10t-5t² = 0
=> t² - 2t - 10 = 0
(use formula)
=> t = -2.32 s (rejected) or
=> t = 4.32 s
(d)
at h = 30 m
=> 50+10t-5t² = 30
=> t² - 2t - 4 = 0
(use formula)
=> t = -1.24 s (rejected) or
=> t = 3.24 s
.
at start, ball at top of building
=> t = 0
h = 50+10t-5t² = 50
height = 50m
(b)
at top of building again,
=> 50+10t-5t² = 50
=> 5t² - 10t = 0
=> t(t - 10) = 0
=> t = 0 or t = 10 s
at t = 10 s
(c)
reach ground => h = 0 m
=> 50+10t-5t² = 0
=> t² - 2t - 10 = 0
(use formula)
=> t = -2.32 s (rejected) or
=> t = 4.32 s
(d)
at h = 30 m
=> 50+10t-5t² = 30
=> t² - 2t - 4 = 0
(use formula)
=> t = -1.24 s (rejected) or
=> t = 3.24 s
.
@snell thanks for helping me :)
np
hope u understand
.
hope u understand
.
See 1 Answer
Hi it's been answered by snell thanks :)
360 Tutoring Program