Answer:
(a) W=1.20×10⁴J
(b) U= -5.46×10⁴J
(c) Q= -4.26×10⁴J
Explanation:
Given that student does 1.20×10⁴J work
(a) W=1.20×10⁴J
Work done by student,so positive sign
During the process, his internal energy decreases by 5.46×10⁴J.
(b) U= -5.46×10⁴J.
As the Energy decreases therefore negative sign
For (c) Q
We know the formula
Answer:
Acceleration,
Explanation:
It is given that,
Initial velocity of the car, u = 10 m/s (in right)
Final velocity of the car, v = -5 m/s (in left)
Time taken, t = 10 s
Let a is the acceleration of the car. It can be calculated using the equation of kinematics. The equation is as :
So, the acceleration of the car is . Hence, this is the required solution.
Answer:
3675 J
Explanation:
Gravitational Potential Energy = × mass × g × height
( g is the gravitation field strength )
Mass = 50 kg
G = 9.8 N/kg ( this is always the same )
Height = 15 m
Gravitational Potential Energy = × 50 ×9.8 × 15
= 3675 J
Answer:
Acceleration = -0.75 m/s²
Explanation:
Given the following data;
Initial velocity = 24 m/s
Final velocity = 15 m/s
Time = 12 seconds
To find the acceleration of the automobile;
Acceleration can be defined as the rate of change of the velocity of an object with respect to time.
This simply means that, acceleration is given by the subtraction of initial velocity from the final velocity all over time.
Hence, if we subtract the initial velocity from the final velocity and divide that by the time, we can calculate an object’s acceleration.
Mathematically, acceleration is given by the equation;
Substituting into the formula, we have;
Acceleration = -0.75 m/s²
Therefore, the automobile is decelerating because its final velocity is lesser than its initial velocity, leading to a negative value.