Complete Question:
One simple model for a person running the 100 m dash is to assume the sprinter runs with constant acceleration until reaching top speed, then maintains that speed through the finish line. If a sprinter reaches his top speed of 11.5 m/s in 2.24 s, what will be his total time?
Answer:
total time = 6.24 s
Explanation:
Using the equation of motion:
v = u + at
initial speed, u = 0 m/s
v = 11.5 m/s
t = 2.24 s
11.5 = 0 + 2.24a
a = 11.5/2.24
a = 5.13 m/s²
For the total time spent by the sprinter:
s = ut + 0.5at²
100 = 0.5 * 5.13 * t²
t² = 100/2.567
t² = 38.957
t = √38.957
t = 6.24 s
Answer:
15 N and 3.061
Explanation:
From the question,
The minimum force of friction to keep the book from sliding = 15 N.
using
F = mgμ................. Equation 1
Where F = Frictional Force, m = mass of the book, g = acceleration due to gravity, μ = coefficient of friction.
make μ the subject of the equation
μ = F/mg............... Equation 2
Given: F = 15 N, m = 0.5 kg, g = 9.8 m/s²
Substitute into equation 2
μ = 15(0.5×9.8)
μ = 15/4.9
μ = 3.061
Hence the coefficient of friction to keep the book from sliding = 3.061
Answer:
potential energy = mgh
= 400÷1000 × 10× 4÷100
= 0.4 × 10 × 0.04
=4/10 ×10×4/100
= 4/10 × 4/10
=16/100
= 0.16 joules
m1 (400) stretches 4cm
m1 (100g) stretches 1cm
so, m2(800g) stretches 8 cm
potential energy of m2 = mgh
= 800/1000 ×10×8/100
= 0.8 × 0.8
=8/10 ×8/10
= 64/100
=0.64 joules
Ratio of s1 to s2
16/100 ÷ 64/100
= 1:4 ( answer)
Answer:
An estuary is the area where a river meets the sea or ocean, where fresh water from the river meets salt water from the sea.
Answer:6m/s^2
Explanation:
Mass =3kg
Force=18N
Acceleration =force ➗ mass
Acceleration =18 ➗ 3
Acceleration =6
Acceleration =6m/s^2
