Answer:
False statement = There must be a non-zero net force acting on the object.
Explanation:
An object is moving at a constant speed along a straight line. If the speed is constant then its velocity must be constant. We know that the rate of change of velocity is called acceleration of the object i.e.

a = 0
⇒ The acceleration of the object is zero.
The product of force and acceleration gives the magnitude of force acting on the object i.e.
F = m a = 0
⇒ The net force acting on the object must be zero.
So, the option (a) is not true. This is because the force acting on the object is zero. First option contradicts the fact.
Answer:

Explanation:
Given that

From the diagram

By differentiating with time t

When x= 10 m

θ = 64.53°
Now by putting the value in equation



Therefore rate of change in the angle is 0.038\ rad/s
Answer:
In my opinion I think that the answer is C sorry If I get this wrong.
Answer:
16. 68.18 Km/h
17. 3 miles.
Explanation:
16. Determination of the speed
Distance travelled = 150 Km
Time = 2.2 hours
Speed =?
Speed is simply defined as the distance travelled with time. Mathematically, it is expressed as:
Speed = Distance / time
With the above formula, we can obtain the speed as follow:
Distance travelled = 150 Km
Time = 2.2 hours
Speed =?
Speed = Distance /time
Speed = 150 / 2.2
Speed = 68.18 Km/h
17. Determination of the distance.
Speed = 3 mph
Time = 1 hour
Distance =?
Speed = Distance /time
3 = distance / 1
Distance = 3 miles
Choice-a is a very rubbery, imprecise, ambiguous, slippery statement. But it's probably less wrong than any of the other choices on the list.