Answer:
false
Explanation:
it's because of potential
Answer:
Explanation:
given,
speed of the pebble = 14 m/s
height of the building = 31 m
ignoring air resistance
a) horizontally
V_x = 14 m/s
time =
time =
times = 2.52 s
v_y = 9.8 x 2.52
v_y = 24.7 m/s
resultant velocity
=
= 28.39 m/s
b) vertically straight up
max height =
=
= 11.47 m
height covered = 31 + 11.47
= 42.47 m
velocity =
=
= 28.85 m/s
c) vertically down
v² = u² + 2as
v² = 2 × 9.8 × 31 +14²
v² = 803.6
v = 28.35 m/s
<h3><u>
For the aceleration:</u></h3>
First, let's find the resultant, and <u>applicate 2nd law of Newton</u> using the resultant, so:
R = ma
F - Ff = ma
Data:
F = Force = 1150 N
Ff = Friction force = 490 N
m = Mass = 150 kg
a = Aceleraction = ?
Replacing according our data:
1150 N - 490 N = 150 kg * a
660 N = 150 kg * a
660 N / 150 kg = a
a = 4,4 m/s² ← Aceleration of the object
<h3><u>For the normal force:</u></h3>
The normal force IS NOT the resultant force, the normal force's the force between the ground and the object, in another words, is the weight of the object, and for the weight:
w = mg
w = 150 kg * 10 m/s²
w = 1500 N ← Normal force between object and ground.
M=mv
=0.30x5.6
=2.016kgm/s