Answer:
Time, t = 13.34 seconds.
Explanation:
Given the following data;
Initial velocity, u = 85km/hr to meters per seconds = 85*1000/3600 = 23.61 m/s
Final velocity, v = 45km/hr to meters per seconds = 45*1000/3600 = 12.5 m/s
Acceleration, a = -3 km/hr/sec to meters per seconds square = -3*1000/3600 = -0.833m/s²
To find the time;
Acceleration = (v - u)/t
-0.833 = (12.5 - 23.61)/t
-0.833t = -11.11
t = 11.11/0.833
Time, t = 13.34 seconds.
Answer:
Explanation:
Distance and direction of an object's change in position from a starting point. Displacement. 3. Jermaine runs exactly 2 laps around a 400 meter track. What is the displacement? 0 ... David walks 3 km north, and then turns east and walks 4 km. ... A person walks 50 meters directly north, stops, and then travels 32 meters
Work done on the crate is 1411.2 J
Explanation:
Work done is defined as the product of force and the distance moved by the object. The unit of work done is in joules and denoted by the symbol J.
Work done = F * d
where F represents the force and d represents the distance moved by the object.
mass = 72 kg , distance moved by the object is given by 2.0 m
Force F = mass * gravity = 72 * 9.8
= 705.6 N =706 N.
Work done = 706 * 2.0 = 1412 J.
Answer:
Time, t = 0.87 seconds
Explanation:
Given that,
Initial velocity of the object, u = 4.3 m/s
The coefficient of kinetic friction between horizontal tabletop and the object is 0.5
We need to find the time taken by the object for the object to come to rest i.e. final velocity will be 0.
Using first equation of motion to find it as :
a is the acceleration, here, 
So, the time taken by the object to come at rest is 0.87 seconds. Hence, this is the required solution.
