3. 1a i) KE = ½ x mass x speed2
1a i) KE = ½ x kg x (m/s)2
1a i) KE = ½ x kg x (m/s)2
1a i) KE = ,000 J
1a ii) KE = ½ x mass x speed2
1a ii) KE = ½ x kg x (m/s)2
1a ii) KE = ½ x kg x (m/s)2
1a i) KE = J

4. 1b KE = ½ x mass x speed2
1b x KE = m x V2
1b x KE = V 2 m
1b x KE = V m
1b x 2 x 36,000 J = m/s
500 kg

5. 2a. i) The elastic potential energy store increases
The chemical energy store of the person decreases.
2aii) The elastic potential energy store decreases
The kinetic energy store of the object increases.
KE = ½ m V 2
2b i) ∆GPE = weight x ∆ height
2b i) ∆GPE = N x m
1b x KE = V m
2b i) ∆GPE = J
2b ii) ∆GPE = ∆ KE = 10 J
1b x 10 J = m/s
0.2 kg

6. 3a KE = Work done by brakes
KE = Fs
360, = F 100
3,600 N = F
3b ,000 J = ½ x m kg x (m/s)2
3b ,000 J = ½ x m kg x (m/s)2
3b ,000 J = ½ x m kg x (m/s)2
3b , = ½ x kg
450

7. ∆ elastic PE = ½ k e2
2b i) ∆ elastic PE = ½ x x
2b i) ∆ elastic PE = J