It is positive if that's what you are asking.
The answer would be B. :)
Answer:
9) This is a case of deceleration
10)-0.8 ms-2
b) acceleration is the change in velocity with time
11)
a) 100 ms-1
b) 100 seconds
12) 10ms-1
13) more information is needed to answer the question
14) - 0.4 ms^-2
15) 0.8 ms^-2
Explanation:
The deceleration is;
v-u/t
v= final velocity
u= initial velocity
t= time taken
20-60/50 =- 40/50= -0.8 ms-2
11)
Since it starts from rest, u=0 hence
v= u + at
v= 10 ×10
v= 100 ms-1
b)
v= u + at but u=0
1000 = 10 t
t= 1000/10
t= 100 seconds
12) since the sprinter must have started from rest, u= 0
v= u + at
v= 5 × 2
v= 10ms-1
14)
v- u/t
10 - 20/ 25
10/25
=- 0.4 ms^-2
15)
a=v-u/t
From rest, u=0
8 - 0/10
a= 8/10
a= 0.8 ms^-2
Answer:
3600 kg
Explanation:
From the question,
Density = Mass/Volume
D = M/V.............................. Equation 1
Where D = Density of the substance, M = mass of the substance, V = Volume of the subtance.
Make M the subject of the equation
M = D×V ............................ Equation 2
Given: D = 1200 kg/m³, V = 3 m³.
Substitute these values into equation 2
M = 1200×3
M = 3600 kg.
Hence the mass of the substance is 3600 kg
