Answer:
98.4 N
Explanation:
Given that the body weighs 800 N on earth.
Thus,
Weight = mass x acceleration due gravity
i.e W = mg
800 = m x 10
m =
= 80 kg
The mass of the body is 80 kg.
To be able to determine its weight on the planet, we have to first calculate the gravitational pull of the planet.
But,
g =
Where: G is the Newton's universal gravitation, M is the mass of the planet and r is the radius of the planet.
g =
=
= 1.2275
g = 1.23 m/
Thus,
Weight of the body on the planet = mg
= 80 x 1.23
= 98.4 N
The weight of the body on the planet is 98.4 N
Answer:
(a)
vf_1s = 5.19 m/s
h_1s = 10.095 m
vf_4s = 24.23 m/s
h_4s = 4.49 m (below railing)
(b)
vi = 9.9 m/s
(c)
t = 1.53 s
h = 34.41 m
Explanation:
(c)
First, we will use the 1st equation of motion to find the time to attain the highest point:
where,
t = time to attain maximum height = ?
vf = final velocity = 0 m/s (ball momentarily stops at highest point
vi = initial velocity = 15 m/s
g = - 9.81 m/s (for upward motion)
<u>t = 1.53 s</u>
Now, for the height attained we will use the 2nd equation of motion:
<u>h = 34.41 m</u>
(b)
using the 3rd equation of motion for a height of 5 m:
<u>vi = 9.9 m/s</u>
<u></u>
(c)
At t = 1 s:
<u>vf_1s = 5.19 m/s</u>
<u></u><u></u>
<u>h_1s = 10.095 m</u>
<u></u>
At t = 4 s:
Since the ball covers the maximum height of 34.41 m in 1.53 s and then starts moving downward.
Therefore for the remaining 4 s - 1.53 s = 2.47 s, the initial velocity will be 0 m/s at the highest point and the value of g will be positive due to downward motion.
<u>vf_4s = 24.23 m/s</u>
<u></u><u></u>
now, for the position with respect to railing:
<u>h_4s = 4.49 m (below railing)</u>
<u></u>
Answer:
Net external force acting on the rock when it is at the top of its trajectory is force due to gravity (mg).
Explanation:
The forces acting on a rock thrown up are force due to gravity and air resistance. Air resistance is directly proportional to velocity of rock, when velocity is zero air resistance is zero. When it is at the top of its trajectory its velocity is zero. So air resistance is also zero. Hence only gravitational force acts on the rock.
Net external force acting on the rock when it is at the top of its trajectory is force due to gravity (mg).
Answer:
wildlife reserves are not available for camping...but you can camp at a skatepark
Answer:
4.32
Explanation:
The centripetal acceleration of any object is given as
A(cr) = v²/r, where
A(c) = the centripetal acceleration
v = the linear acceleration
r = the given radius, 1.9 m
Since we are not given directly the centripetal acceleration, we'd be using the value of acceleration due to gravity, 9.8. This means that
9.8 = v²/1.9
v² = 1.9 * 9.8
v² = 18.62
v = √18.62
v = 4.32 m/s
This means that, the minimum speed the cup must have so as not to get wet or any spill is 4.32 m/s