Answer:
First of all the attack is gonna die because its 2020 who throws a rock up over a wall to kill someone(cavemen) and
it's gonna be ↓
explanation:
An attacker at the base of a castle wall 3.60 m high throws a rock straight up with speed 8.00 m/s from a height of 1.70 m above the ground.
(a) Will the rock reach the top of the wall?
(b) If so, what is its speed at the top? If not, what initial speed must it have to reach the top?
(c) Find the change in speed of a rock thrown straight down from the top of the wall at an initial speed of 8.00 m/s and moving between the same two points.
(d) Does the change in speed of the downward-moving rock agree with the magnitude of the speed change of the rock moving upward between the same elevations? Explain physically why it does or does not agree.
Answer:
only E is true
Explanation:
A) to find out if it would fall 4x as fast by 2x the time we can look at the formula for free fall:
for free fall the Y = g where Y is the distance fallen, g is gravity and t is time
so since the rate at which an object falls is the same (gravity stays the same) it will not fall faster with any alteration
B) An object would fall half the distance if you double the time
here we may need to check with an example:
lets say we fall for 2 seconds in the first and 4 in the second:
Y= 1/2 (9.8) (2)^2 gives 19.6m fallen
Y= 1/2 (9.8) (4)^2 gives 78.4m fallen
from this we can see that doubling the time does not half the distance
C) all objects fall at the same rate no matter their mass so this statement is false
D) from the example above we see again that doubling time does not double the distance
E) this statement is true
Answer:
The speed and direction of the two players immediately after the tackle are 3.3 m/s and 53.4° South of West
Explanation:
given information:
mass of fullback, = 92 kg
speed of full back, = 5.8 to south
mass of lineman, =110 kg
speed of lineman, = 3.6
according to conservation energy,
assume that the collision is perfectly inelastic, thus
initial momentum = final momentum
= '
m₁v₁ = (m₁+m₂)'
' = m₁v₁/(m₁+m₂)
= (92) (5.8)/(92+110)
= 2.64 m/s
= '
m₂v₂ = (m₁+m₂)'
' = m₁v₁/(m₁+m₂)
= (110) (3.6)/(92+110)
= 1.96 m/s
thus,
' = √'²+'²
= 3.3 m/s
then, the direction of the two players is
θ = 90 - tan⁻¹('/')
= 90 - tan⁻¹(1.96/2.64)
= 53.4° South of West
Its acceleration is 10ft/ sec
Answer:
Or in the other way:
Explanation:
For this case we need to remember that hectare is a measure of area. And we have the following ratios:
We can convert this into
We can convert this into
By dimensional analysis we assume that we can find the ratio in terms of distance like this:
And if we find the ratios in terms of distance we got:
Or in the other way: