Explanation :
We know that the slope of velocity -time graph gives the acceleration. Acceleration of an object is defined as the rate of change of velocity i.e.
Suppose a driver suddenly applies brakes. In this case the initial velocity of his or her vehicle is more and the final velocity is less.
So, the acceleration is negative in this case i.e. the object is decelerating.
A negative slope on the velocity versus time graph indicates that an object is not accelerating. This statement is false as the object is decelerating.
Answer:
2.7ohms
Explanation:
Given parameters:
Voltage of the battery = 12V
Current = 4.5A
Unknown:
Resistance of the resistor = ?
Solution:
From Ohm's law, we know that;
V = IR
V is the voltage
I is the current
R is the resistance
So;
R = = = 2.7ohms
Answer:
Explanation:
Impulse on an object is given by .
However, it's also given as change in momentum (impulse-momentum theorem).
Therefore, we can set the change in momentum equal to the former formula for impulse:
.
Momentum is given by . Because the truck's mass is maintained, only it's velocity is changing. Since the truck is being slowed from 26.0 m/s to 18.0 m/s, it's change in velocity is 8.0 m/s. Therefore, it's change in momentum is:
.
Now we plug in our values and solve:
(two significant figures).