________b_____ 7 km east
|
| 2km north.
|a
|
°
pythagorean theorem : ✓a² + b² = c²
c² = a² + b² = 4 + 49 = 53
c = ✓53 km
displacement = c = ✓53 km
distance = 10 + 3 + 2 = 15 km
(a) 154.5 N
Let's divide the motion of the sprinter in two parts:
- In the first part, he starts with velocity u = 0 and accelerates with constant acceleration
for a total time
During this part of the motion, he covers a distance equal to
, until he finally reaches a velocity of
. We can use the following suvat equation:

which reduces to
(1)
since u = 0.
- In the second part, he continues with constant speed
, covering a distance of
in a time
. This part of the motion is a uniform motion, so we can use the equation
(2)
We also know that the total time is 10.0 s, so

Therefore substituting into the 2nd equation

From eq.(1) we find
(3)
And substituting into (2)

Solving for t,

So from (3) we find the acceleration in the first phase:
And so the average force exerted on the sprinter is

b) 14.5 m/s
The speed of the sprinter remains constant during the last 55 m of motion, so we can just use the suvat equation

where we have
u = 0
is the acceleration
is the time of the first part
Solving the equation,

Answer:
We weigh more on Earth because of gravity. Gravity pulls our body towards the Earh and hence our mass is more. But in space there is no gravity and thus the mass will accordingly be less due to absence of centre of gravity. Thus, mass is affected by the location of a body or an object in space.
Explanation:
Answer:
The new volume of the ballon will be 13.345 L
Explanation:
Charles's Law consists of the relationship that exists between the volume and the temperature of a certain quantity of ideal gas, which is maintained at a constant pressure, by means of a constant of proportionality that is applied directly. For a given sum of gas at a constant pressure, as the temperature increases, the volume of the gas increases and as the temperature decreases, the volume of the gas decreases.
Charles's law is a law that says that when the amount of gas and pressure are kept constant, the quotient that exists between the volume and the temperature will always have the same value:

It is possible to assume that you have a certain volume of gas V1 that is at a temperature T1 at the beginning of the experiment. If you vary the volume of gas to a new value V2, then the temperature will change to T2, and it will be true:

In this case:
- V1= 17 L
- T1= 200 K
- V2= ?
- T2= 157 K
Replacing:

Solving:

V2= 13.345 L
<u><em>The new volume of the ballon will be 13.345 L</em></u>
Vf=(35.0)+(-9.8)(2)
the answer would be 15.4 m/s