Use Newton's 2nd law of motion.
Here it is:
Force = (mass) x (acceleration)
= (80 kg) x (-5 m/s²)
= -400 Newtons .
I called the acceleration negative because the player is slowing down.
The force comes out negative because it's in the direction opposite to
his motion.
Answer:
1.08 s
Explanation:
From the question given above, the following data were obtained:
Height (h) reached = 1.45 m
Time of flight (T) =?
Next, we shall determine the time taken for the kangaroo to return from the height of 1.45 m. This can be obtained as follow:
Height (h) = 1.45 m
Acceleration due to gravity (g) = 9.8 m/s²
Time (t) =?
h = ½gt²
1.45 = ½ × 9.8 × t²
1.45 = 4.9 × t²
Divide both side by 4.9
t² = 1.45/4.9
Take the square root of both side
t = √(1.45/4.9)
t = 0.54 s
Note: the time taken to fall from the height(1.45m) is the same as the time taken for the kangaroo to get to the height(1.45 m).
Finally, we shall determine the total time spent by the kangaroo before returning to the earth. This can be obtained as follow:
Time (t) taken to reach the height = 0.54 s
Time of flight (T) =?
T = 2t
T = 2 × 0.54
T = 1.08 s
Therefore, it will take the kangaroo 1.08 s to return to the earth.
For the rest 3 km
Bholu need to run in 5 minutes so
He need to 3 × 1000 / 5 × 60 m/s
3000/ 300 = 10 m/s
So , his speed should be 1 m/s to reach in 5 minute
mark as brainliest 5 star
To solve this exercise it is necessary to apply the concepts related to Work and Kinetic Energy. Work from the rotational movement is described as

In the case of rotational kinetic energy we know that

PART A)
is given in revolutions and needs to be in radians therefore


Replacing in the work equation we have to



PART B) From the torque and moment of inertia it is possible to calculate the angular acceleration and the final speed, with which the kinetic energy can be determined.

Rearrange for the angular acceleration,



From the kinematic equations of angular motion we have,




In this way the rotational kinetic energy would be given by



Answer:
30 mins
Explanation:
speee=distance/time
300m/h=15m/time
time=15miles/300miles/hous=1/2 hours=30 mins